Date:___________ Created by: Loren L. Spencer Main Idea Determining whether a number is positive or negative Through Integer Rules Integer definition—Whole numbers and their opposites-- (Positive and Negative numbers) Rule 1: The sign in front of the number tells us whether or not the number is positive or negative. a. If the sign is a (+), the number is positive. Example: b. If the sign is a (-), the number is negative. **(Hint: Always circle the sign and its number.) Rule 2: If the number does not have a sign, the number is always positive. Rule 3: Positive numbers are always greater than negative numbers. **(Hint: As you move to the left on the number line the numbers get smaller. As you move to the right the numbers get larger.) Example: -6×7= Multiplying and dividing with integers Rule 1: If the signs of both numbers are the same, the answer is positive. Example: -2×-2= Example: -6÷-3= Rule 2: If the signs of both numbers are different, the answer is negative. Example: 20÷-4= 1 Date:___________ Created by: Loren L. Spencer Main Idea Rules for adding and subtracting integers Through More Integer Rules Example: 3+4= Rule 1: If the signs of both numbers are the same, add the numbers and keep the sign. Example: -6-2= Rule 2: If the signs of both numbers are different, subtract the numbers and keep the sign of the number with the larger absolute value. Steps to use when two signs are side by side Step 1: Circle the two signs that are next to each other like this. Step 2: Now turn the (2) two signs that are next to each other into (1) one sign. Step 3: Rewrite the equation. Example: -2+4= Example: 6-9= ***To solve this type of problem: Refer to the multiplication and division rules for integers. You must turn the (2) two signs into (1) one sign. - Example: -6+ 2= - Example: 3- 5= Step 4: Solve using the addition and subtraction rules for integers. 2 Date:___________ Main Idea Adding and Subtracting Created by: Loren L. Spencer Through Decimal Operations Example: .06+2.375= Step 1: Rewrite the Problem so that the numbers stack. (Always line up the decimals when you add and subtract) Sometimes it helps to draw a vertical line through the decimals. Step 2: Add or subtract like normal. Example: 8.25-6.375= Multiplying Decimals Example: .22×.675= Step 1: Multiply the problem like there are no decimals in the problem. Step 2: Count the number of places “cheeks” to the right of the decimal(s). Example: 3.14×15= Step 3: Now go back to your answer in Step 1. Starting from the left and moving towards the right count the same number of places as you had in Step 2. 3 Date:___________ Main Idea Loops & Mixed Numbers Created by: Loren L. Spencer Through Adding and Subtracting Mixed Numbers Step 1: Add or subtract the whole numbers. Step 2: Circle the denominator on the left and draw a loop to the right and place the denominator over itself. Step 3: Circle the denominator on the right and draw a loop to the left and place the denominator over itself. Step 4: Multiply straight across. (The denominators should be equal) Step 5: Add or subtract the numerators and keep the denominators the same. Step 6: If the answer is an improper fraction simplify by division. Step 7: Reduce 4 Date:___________ Main Idea Multiplying Mixed Numbers Created by: Loren L. Spencer Through Multiplying and Dividing Mixed Numbers Step 1: To multiply or divide mixed numbers you need to turn the mixed numbers into improper fractions. A. For the left Mixed number, Multiply the denominator and the whole number and add the numerator—this total becomes the numerator for the improper fraction. B. Follow the above step for the right Mixed number. Step 2: Multiply straight across. Step 3: If the answer is an improper fraction simplify by division. Step 4: Reduce 5 Date:___________ Main Idea Dividing Mixed Numbers Created by: Loren L. Spencer Through Multiplying and Dividing Mixed Numbers Step 1: To multiply or divide mixed numbers you need to turn the mixed numbers into improper fractions. A. For the left Mixed number, Multiply the denominator and the whole number and add the numerator—This becomes the numerator for the improper fraction. B. Follow the above step for the right Mixed number. Now Remember--Dividing Fractions is as easy as pie, Flip the 2nd and multiply. Step 2: Take the reciprocal of the 2nd fraction. Flip it Step 3: Multiply straight across. Step 4: If the answer is an improper fraction simplify by division. Step 5: Reduce 6 Date:___________ Main Idea Dividing Decimals Created by: Loren L. Spencer Through Decimal Operations Example: .0675÷2.5= Step 1: Place the 1st number in “the house” (the division symbol.) and place the 2nd outside. Step 2: Move the decimal on the divisor (the number outside of the house) to the right to make a whole number. Step 3: Move the decimal on the divisor (the number inside the house) to the right the same number of places “cheeks.” Example: 15.7÷3.14= Step 4: Draw a vertical line through the decimal and bring the decimal on top of the house. (the line eliminates sloppy mistakes) Step 5: Now you can divide like a normal division problem. 7 Date:___________ Created by: Loren L. Spencer Main Idea Converting Decimals to Percents Rule 1: If there is no decimal shown then the decimal is on the right side. Through Converting between Decimals, Fractions, and Percents Percent—a ratio/fraction comparing a number to 100 Remember: the % sign has two zeros, so you must Step 1: Move the decimal place 2 “cheeks” to the right. Remember: D P Step 2: If there are no digits/numbers in a cheek, fill with zeros—No empty cheeks Step 3: Place a percent sign to the right of the last number. move the decimal 2 places Example: Change 22 to a percent Decimal D Percent P Example: Change .0735 to a percent Decimal D Percent P Example: Change .0003 to a percent Converting Percents to Decimals Decimal D Percent P Rule 1: It is only a percent if there is a percent sign. Rule 2: If there is no decimal shown then the decimal is on the right side. Step 1: Move the decimal place 2 “cheeks” to the Left. Remember: D P Step 2: If there are no digits/numbers in a cheek, fill with zeros—No empty cheeks Example: Change 125% to a decimal Decimal D Percent P Example: Change .0034% to a decimal Decimal D Percent P Example: Change 7.21% to a decimal Decimal D Percent P 8 Date:___________ Created by: Loren L. Spencer Main Idea Through Converting Fractions to Decimals Converting between Decimals, Fractions, and Percents Cowboy 𝟑 Example: 𝟖 Step 1: Divide the numerator by the denominator. The numerator goes in the house. Example: Horse 𝟐 𝟓 or 𝟑 𝟏 Remember: The cowboy sits on the saddle on top of the horse. When he gets home the cowboy goes inside, and the horse stays outside. Memorize: =.10 so that 𝟏𝟎 =3×.10=.30 𝟏𝟎 & multiply 𝟏 𝟓 = . 125 so that =5×.125=.625 by the 𝟖 𝟏 numerator 𝟓 𝟏 𝟒 𝟏 Step 2: Move the decimal place 2 “cheeks” to the right. Remember: D =.25 so that =7×.25=1.75 𝟒 𝟓 = .333 so that =5×.333=1.666 𝟑 𝟑 𝟏 𝟗 = .50 so that =9×.50 =4.50 𝟐 𝟐 Converting Fractions to Percents Step 1: Change the fraction into a decimal by dividing the numerator by the denominator. The numerator goes in the house. =.20 𝟖 𝟒 so that =4×.20=.80 𝟓 𝟕 Example: Example: 𝟑 = 𝟏𝟓 𝟐 𝟑 = P Step 3: If there are no digits/numbers in a cheek, fill with zeros—No empty cheeks Step 3: Place a percent sign to the right of the last number. Or by ball bat 𝟑 = 𝟏𝟓 𝟐 𝟑 𝟏𝟎𝟎% = 𝟏𝟎𝟎% 9 Date:___________ Created by: Loren L. Spencer Main Idea Converting Decimals to Fractions Through Converting between Decimals, Fractions, and Percents Fraction: a part of a whole, in the form of 𝑵 𝑫 Denominator: The bottom number of a fraction which represents the number of parts in the whole Numerator: The top number of a fraction Step 1: If there is a whole number (the number to the left of the decimal bring) it down. It will stay to the left of the fraction. Example: .375 Step 2: The numbers to the right of the decimal will become the numerator. Place them over 1. Step 3: Count the places “cheeks” to the right of the decimal in the original problem and place that many zeros to the right of the one in the denominator. Example: 2.56 Step 4: Reduce 10 Date:___________ Created by: Loren L. Spencer Main Idea Ordering Rational Numbers 3 major ways to order rational Numbers: 1. Make everything a Decimal 2. Make everything a Percent 3. Make everything a Fraction (Least preferred) Through Ordering Decimals, Fractions, and Percents Rational Number: Any number that can be expressed as the ratio/fraction of two integers. Example: 1/3 Step 1: Using the rules above change everything into a decimal Step 2: Stack the numbers by lining up the decimals. (You should be able to draw a vertical line through all of the decimals) 20% .3 3% Example: 1/5 5% .35 3.5% Step 3: Now add zeros to the ends to make every number the same length. Step 4: Add a dollar sign in front of each number and determine which is the largest. Write it down. Then choose the next largest. (Remember to mark out each one as you go.) Example: 62.5% 2/3 75% 1/2 7/10 Note 1: You can convert all the numbers to percents and follow the above steps. This is an equally good method and is often preferred by my students Note 2: I do not recommend converting to fractions as it is difficult to find a common denominator. Remember: A positive number is always greater than a negative one. 11 Date:___________ Created by: Loren L. Spencer Main Idea Through Multiplying fractions Fraction Operations Improper Fraction: A fraction which has a numerator greater than or equal to the denominator. Step 1: Multiply straight across Example: Multiply the denominator times the denominator and multiply the numerator times the numerator. Step 2: If the answer is an improper fraction, simplify by division Step 3: Reduce Example: Example: 𝟑 𝟓 𝟓 𝟑 𝟖 𝟓 𝟒 × = 𝟕 𝟏 × 𝟏𝟎= 𝟒 × 𝟔= Hint: If you are multiplying or dividing fractions and a whole number, always place the whole number over 1. Example: 𝟕 𝟖 × 𝟑= 12 Date:___________ Created by: Loren L. Spencer Main Idea Through Dividing Fractions More Fraction Operations Dividing Fractions is as easy as pie, Flip the 2nd and multiply. Example: 𝟒 𝟓 𝟔 ÷ 𝟕= Step 1: Take the reciprocal of the 2nd fraction. Flip it Step 2: Multiply straight across Multiply the denominator times the denominator and multiply the numerator times the numerator. Step 3: If the answer is an improper fraction, simplify by division Example: Example: 𝟒 𝟓 𝟑 𝟖 𝟔 ÷ 𝟕= ÷ 𝟓= Step 4: Reduce Example: 𝟓 𝟔 𝟐 ÷ 𝟑= Hint: If you are multiplying or dividing a fraction and a whole number, always place the whole number over 1. 13 Date:___________ Created by: Loren L. Spencer Main Idea Loops Rule 1: To add & subtract fractions, you must have like denominators. Step 1: Circle the denominator on the left and draw a loop to the right and place the denominator over itself. Through Adding and Subtracting Fractions Example: Example: 𝟑 𝟖 𝟐 𝟑 𝟐 +𝟕 𝟓 +𝟕 Step 2: Circle the denominator on the right and draw a loop to the left and place the denominator over itself. Example: 𝟓 𝟔 - 𝟑 - 𝟕 𝟓 Step 3: Multiply straight across. (The denominators should be equal) Step 4: Add or subtract the numerators and keep the denominators the same. Example: 𝟑 𝟒 𝟗 Step 5: If the answer is improper simplify by division. Step 6: Reduce 14 Date:___________ Created by: Loren L. Spencer Main Idea Through Exponents with Positive Bases Exponents and Square Roots 4 Definition: Exponent/power Example: 5 Step 1: Re-write in Expanded form Example: (6) 3 Step 2: Multiply Exponents with Negative Bases Example: (-4) 3 Example: (-3) 4 Rule 1: If the base is negative and the exponent is an even number the answer will be positive. Rule 2: If the base is positive and the exponent is an odd number the answer will be negative. Square Roots Definition: Square Root Step 1: Make the Perfect squares chart Step 2: Determine where the number is located. Be careful The answer is in the first column. This the square root sign it is not a division symbol Example: What two integers is the 200 between? Example: Which is the closest to 90 a) 9.3 b) 9.4 c) 9.5 d) 9.6 15 Date:___________ Created by: Loren L. Spencer Main Idea Scientific Notation Rule 1: To be in Scientific Notation, you must have one and only one number not equal to zero to the left of the decimal. Rule 2: To be in Scientific Notation it will always be written as some number x10 Power Converting from Standard Form to Scientific Notation Step 1: Draw a line where the decimal is going to go. Don’t Forget Rule 1. Step 2: Write the number with its new decimal location x10. (Zeros at the end of the number are not needed.) Refer to example Step 3: Determine the sign of the exponent negative or positive and write it above and to the right of the 10. (Hint: If there is a zero to the right of the decimal, the exponent will be negative) Step 4: Find the value of the exponent by counting the number of cheeks from the decimal to the line you drew. Place the exponent next to the sign you wrote above base 10. Through Scientific Notation Correct Examples: a) 3.1234 x 108 b) 2.36 x 10-7 Non-examples---These are WRONG!!! 1. 14.256 x 105 2. 0.2345 x 10-8 3. 1.23 x 1-9 4. 8.756 Example 1: The area of an ecological reserve is 450,000 square acres. How is this area expressed in scientific notation? e) 4.5 x 10-5 square acres f) 45 x 10-5 square acres g) 450 x 103 square acres h) 4.5 x 105 square acres Example 2: A certain bacterium measures approximately 0.000015 millimeters in length. How is this expressed in scientific notation? a) 1.5 x 10 5 mm b) 1.5 x 10-5 mm c) 1.5 x 10-4 mm d) 15 x 106 mm 16 Date:___________ Created by: Loren L. Spencer Main Idea Through Converting from Scientific Notation to Standard Form Negative Exponents Hint: If the exponent is negative the resulting standard form number will be less than 1. There will be no whole numbers to the left of the decimal Step 1: Move the decimal the number of places “cheeks” to the left indicated by the exponent. Fill all empty cheeks with a zero. Scientific Notation Example 3: The diameter of a human red blood cell is 7.65 x 10-3 millimeters. Which represents this number in standard form? a) 0.000765 mm b) 7.65000 mm c) 0.00765 mm d) 7,650mm Step 2: Re-write the new number without the X 10 Positive Exponents Step 1: Move the decimal the number of places “cheeks” to the right indicated by the exponent. Fill all empty cheeks with a zero. Step 2: Re-write the new number without the X 10 Hint1: If the exponent is positive the resulting standard form number will be greater than 1. There will be at least 1 whole numbers to the left of the decimal. Example 4: The sun’s core temperature reaches close to 2.7 x 107 degrees Fahrenheit. Which of the following represents this temperature in standard notation? º a) 270,000 F º b) 2,700,000 F º c) 27,000,000 F º d) 270,000,000 F Hint2: If the exponent is negative, there will be no whole number to the right of the decimal. 17 Date:___________ Created by: Loren L. Spencer Main Idea next to the sign you wrote above base 10. Through Scientific Notation Rule 1: To be in Scientific Notation, you must have one and only one number not equal to zero to the left of the decimal. Rule 2: To be in Scientific Notation it will always be written as some number x10 Power Converting from Standard Form to Scientific Notation Step 1: Draw a line where the decimal is going to go. Don’t Forget Rule 1. Scientific Notation Correct Examples: a) 3.1234 x 108 b) 2.36 x 10-7 Not Correct 5. 14.256 x 105 6. 0.2345 x 10-8 7. 1.23 x 1-9 8. 8.756 Example: Step 2: Write the number with its new decimal location x10. (Zeros at the end of the number are not needed.) Refer to example Step 3: Determine the sign of the exponent negative or positive and write it above and to the right of the 10. (Hint: Think about money. Line the standard form numbers decimal up with $1.00 and determine which is greater. If you would prefer to have a $1.00, then the exponent is negative. If you want the standard form number then the exponent is positive. Step 4: Find the value of the exponent by counting the number of cheeks from the decimal to the line you drew. Place the exponent 18 Date:___________ Created by: Loren L. Spencer Main Idea Through Converting from Scientific Notation to Standard Form Scientific Notation Negative Exponents Hint: If the exponent is negative the resulting standard form number will be less than 1. There will be no whole numbers to the left of the decimal Example: Step 1: Move the decimal the number of places “cheeks” to the left indicated by the exponent. Fill all empty cheeks with a zero. Step 2: Re-write the new number without the X 10 Positive Exponents Hint: If the exponent is positive the resulting standard form number will be greater than 1. There will be at least 1 whole numbers to the left of the decimal. Example: Step 1: Move the decimal the number of places “cheeks” to the right indicated by the exponent. Fill all empty cheeks with a zero. Step 2: Re-write the new number without the X 10 19 Date:___________ Main Idea Loops & Mixed Numbers Created by: Loren L. Spencer Through Adding and Subtracting Mixed Numbers Step 1: Add or subtract the whole numbers. Step 2: Circle the denominator on the left and draw a loop to the right and place the denominator over itself. Step 3: Circle the denominator on the right and draw a loop to the left and place the denominator over itself. Step 4: Multiply straight across. (The denominators should be equal) Step 5: Add or subtract the numerators and keep the denominators the same. Step 6: If the answer is an improper fraction simplify by division. Step 7: Reduce 20 Date:___________ Main Idea Multiplying Mixed Numbers Created by: Loren L. Spencer Through Multiplying and Dividing Mixed Numbers Step 1: To multiply or divide mixed numbers you need to turn the mixed numbers into improper fractions. A. For the left Mixed number, Multiply the denominator and the whole number and add the numerator—this total becomes the numerator for the improper fraction. B. Follow the above step for the right Mixed number. Step 2: Multiply straight across. Step 3: If the answer is an improper fraction simplify by division. Step 4: Reduce 21 Date:___________ Main Idea Dividing Mixed Numbers Created by: Loren L. Spencer Through Multiplying and Dividing Mixed Numbers Step 1: To multiply or divide mixed numbers you need to turn the mixed numbers into improper fractions. A. For the left Mixed number, Multiply the denominator and the whole number and add the numerator—This becomes the numerator for the improper fraction. B. Follow the above step for the right Mixed number. Now Remember--Dividing Fractions is as easy as pie, Flip the 2nd and multiply. Step 2: Take the reciprocal of the 2nd fraction. Flip it Step 3: Multiply straight across. Step 4: If the answer is an improper fraction simplify by division. Step 5: Reduce 22 Date:___________ Created by: Loren L. Spencer 23