Course Title: Mathematics for Business &Economics Ahram Canadian University School of Business Administration Dr. Wael Abdel Haleem (Groups B,D&E) & Dr. Nada Ashraf (Groups A&C) Fall 2020 Tutorial # 1 • 100 points / 3 Credit Hours 30 Quizzes & Assignments 30 Midterm exam 40 Final exam Evaluation Grade Process procedure Quizzes 15 Three Quizzes Assignments 15 Five Assignments Mathematics for Business & Economics Course objectives & syllabus The course is designed to help students the use of mathematical tools in solving business & economic problems. Linear equation and its applications in economics such as breakeven, market price and prediction. The main parts of this course are linear programming (the simplex method), probability, derivatives, and integral calculus and its applications in business and economics problems constitute. Mathematics for Business &Economics course contains: • Mathematics Foundations • Mathematical Functions • Linear Equations • Properties of Exponents • Properties of Polynomials • System of Linear Equations (formulation and solution) • Properties of Functions • Solving and Graphing Inequalities • Graphing and Factoring Quadratic Equations • Linear Programming Problems (formulation and solution) Solving Linear Equations in One Variable Form of linear equation ax + b = c a,b,c Constant values X & y two variables (X-1)⁴ One variables 2x +3y =11 4 can be 2, 3 or any other nu.. X⁴+1 NOT linear A solution of a linear equation in one variable is a real number which, when substituted for the variable in the equation, makes the equation true. Ex 1 : 3 OR 4 is a solution of 2x + 4 = 12 Substitute 3 for x 2(3) + 4 = 12 6 + 4 not = 12 False equation Substitute 4 for x 2(4) + 4 = 12 8 + 4 = 12 True equation Properties of equations • Addition Property of Equations (Addition & subtraction ) If a = b, then a + c = b + c and a c = b c • Ex 2: Solve x 4 = 12 X-4 +4 = 12 +4 X=16 Check the answer: 16-4=12 true • Multiplication Property of Equations (Multiplication and division) If a = b and c 0, then ac = bc and Ex 3: Solve 2x + 5 = 19 2x + 5 5 = 19 5 2x = 14 1 1 (2 x) (14) 2 2 X=7 Check the answer: 2(7)+5= 14+5=19 true To solve a linear equation in one variable: 1. Simplify both sides of the equation. 2. Use the addition and subtraction properties to get all variable terms on the left-hand side and all constant terms on the right-hand side. 3. Simplify both sides of the equation. 4. Divide both sides of the equation by the coefficient of the variable. Ex 4: Solve x + 1 = 3(x 5). x + 1 = 3(x 5) Original equation x + 1 = 3x 15 Simplify right-hand side. x = 3x 16 Subtract 1 from both sides. Subtract 3x from both sides. 2x = 16 Divide both sides by 2. x=8 The solution is 8. Check the solution: (8) + 1 = 3((8) 5) 9 = 3(3) True 7 Ex5: Alice has a coin purse containing $5.40 in dimes and quarters. There are 24 coins all together. How many dimes are in the coin purse? Let the number of dimes in the coin purse = d. Then the number of quarters = 24 d. 10d + 25(24 d) = 540 Linear equation 10d + 600 25d = 540 Simplify left-hand side. 10d 25d = 60 15d = 60 d=4 Subtract 600. Simplify right-hand side. Divide by 15. There are 4 dimes in Alice’s coin purse. 8 Ex6: The sum of three consecutive integers is 54. What are the three integers? Three consecutive integers can be represented as n, n + 1, n + 2. n + (n + 1) + (n + 2) = 54 3n + 3 = 54 3n = 51 n = 17 Linear equation Simplify left-hand side. Subtract 3. Divide by 3. The three consecutive integers are 17, 18, and 19. 17 + 18 + 19 = 54. 9 Check. • EX 7: A movie theater sells tickets for $8 each, with seniors receiving a discount of $2. One evening the theater took in $3580 in revenue. If there were 525 tickets sold that evening. It is required to determine how many of each type of ticket were sold that evening? • Let suppose that the number of senior's tickets = S • Then the number of Normal tickets= N = (525-S) • 6S + 8(525-S) = 3580 Convert data to a linear equation • • • • • 6S + 4200- 8S= 3580 Simplify left-hand side 6S-8S=-4200+3580 -2S=-620 S=310 There are 310 senior's tickets AND 215 normal tickets. • Ex 8: Four less than twice some number is 16. Solution: First, choose a variable for the unknown number. Let x represents the unknown indicated by “some number.” 2𝑥 − 4 = 16 2𝑥 − 4 + 4 = 16 + 4 2𝑥 = 20 𝑥 = 10 • Ex 9: When 7 is subtracted from 3 times the sum of a number and 12, the result is 20. • Solution: • Let n represent the unknown number. • 3 𝑛 + 12 − 7 = 20 • 3 𝑛 + 12 = 27 • 𝑛 + 12 = 9 • 𝑛 = −3 • Ex 10: The sum of two consecutive even integers is 46. Find the integers. • Solution: • Let x represents the first even integer and x+2 represents the next even integer • Add the even integers and set them equal to 46. • 𝑥 + 𝑥 + 2 = 46 • 2𝑥 + 2 = 46 • 2𝑥 = 44 • 𝑥 = 22 • Use x + 2 to find the next even integer. • 𝑥 + 2 = 22 + 2 = 24 • The consecutive even integers are 22 and 24. • Ex 11: The sum of two consecutive odd integers is 36. Find the integers. • Solution: • Let x represents the first odd integer and x+2 represents the next odd integer. • Add the two odd integers and set the expression equal to 36. • 𝑥 + 𝑥 + 2 = 36 • 2𝑥 + 2 = 36 • 2𝑥 = 34 • 𝑥 = 17 • Use x + 2 to find the next odd integer. • 𝑥 + 2 = 17 + 2 = 19 • The consecutive odd integers are 17 and 19. • • • • • • • • • • • • • • Ex 12: The sum of three consecutive integers is 24. Find the integers. Solution: Let x represents the first integer Let x+1 represents the second integer Let x+2 represents the third integer Add the 3 integers and set the sum equal to 24. 𝑥 + 𝑥 + 1 + 𝑥 + 2 = 24 3𝑥 + 3 = 24 3𝑥 = 21 𝑥=7 Substitute to find the other two integers. 𝑥+1=7+1=8 𝑥+2=7+2=9 The three consecutive integers are 7, 8 and 9. • Ex 13: A larger integer is 2 less than 3 times a smaller integer. The sum of the two integers is 18. Find the integers. • Solution: • Let x represents the smaller integer and 3x-2 represents the larger integer. • Add the expressions that represent the two integers and set the resulting expression equal to 18. • 𝑥 + 3𝑥 − 2 = 18 • Solve the equation to obtain the smaller integer x. • 4𝑥 − 2 = 18 • 4𝑥 = 20 • • • • 𝑥=5 Use the expression 3x−2 to find the larger integer. 3𝑥 − 2 = (3 ∗ 5) − 2 = 13 The two integers are 5 and 13. • Ex 14: Solve for the variable • 2(x + 5) - 7 = 3(x - 2) • 2𝑥 + 10 − 7 = 3𝑥 − 6 • 2𝑥 + 3 = 3𝑥 − 6 • −𝑥 = −9 •𝑥=9 Ex 15: Example 8: Solve for the variable. 𝟓 𝟏 𝟏 𝒙 + = 𝟐𝒙 − 𝟒 𝟐 𝟐 To get rid of the fractions multiply both sides by 4 5 1 1 4 𝑥 + = 4 2𝑥 − 4 2 2 5𝑥 + 2 = 8𝑥 − 2 −3𝑥 = −4 4 𝑥= 3 Review tutorials on the same day. Thursday 12 Nov 2020, Quiz #1 will be available on Teams from 08:00 pm to 10:00 pm. The duration of quiz#1 is 30 min. Any question?