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NS.09: Fractions, Decimals, Percents, and Ratios Objective: I can convert between decimals, fractions, percents, and ratios. .01 = 1/100 = 1% = 1:100 Mathematical Practices: MP.2: I can use reasoning habits to help me think about numbers in many ways. MP.8: I can solve problems by looking for rules and repeated patterns. Notes: Key Vocabulary: Positive Rational Numbers: Numbers that are greater than zero and can be expressed as a ratio. 6:10 Fraction: part of a whole group. It has a numerator and denominator. ¾ Decimal: a number containing a decimal point, written as base ten. 0.345 Percent: a special ratio that compares a number to 100 using the symbol % Ratio: A comparison of two numbers or measures using division. 2 to 4, 2:4, or 2/4 Convert: to change Notes: Essential Questions: (Skip 4 lines between questions.) 1. What are different ways to express the same value? How do you convert between each value? 2. What is a conversion? Why do you need to convert between values? Note: Fractions, decimals, ratios and percents are different ways to represent the same value. Each conversion requires a specific procedure. Conversion Foldable: 1. Get a sheet of white paper and fold in half horizontally. (like a hamburger) 2. Fold in half again from the folded position. 3. From this position, fold into thirds so you have a small square. To convert (change) a fraction to a decimal, divide the numerator by the denominator. 0.75 3 = 4 3.00 4 Fraction Decimal Change these fractions to decimals: 5 8 2 3 Practice time To convert a decimal to a fraction, use the place value of the last digit to determine the denominator and put the numbers to the right of the decimal point in the numerator. Reduce to lowest terms. 0.75 = 75 100 = 3 4 The 5 is in the hundredths place. Then, reduce to lowest terms. Decimal Fraction Convert the decimals into a fraction: 0.92 2.15 0.37 Let’s try a couple. To convert a decimal to a percent, move the decimal point two places to the right and add the % sign. 0.75 = 75% Decimal Percent Change decimals to percent: 0.67 0.125 1.73 Try these To convert a percent to a decimal, move the decimal point two places to the left and remove the % sign. 75.% = 0.75 Percent Decimal Change the percents to decimals: 44% 59.2% 315% You can do it!!! What are the three ways to write a ratio? Apply what you have learned to convert a decimal and a percent to a ratio. Not too tough, right? Convert these numbers into a ratio: 0.4 76% 0.37 Don’t forget to reduce.