Warm Up Problem of the Day Lesson Presentation Lesson Quizzes.

5-10 Solving Fraction Equations: Multiplication and Division

Warm UpWarm Up

Lesson PresentationProblem of the Day

Lesson Quizzes


Warm UpSolve.1. x – 5 = 17

2. 5x = 125

3. x + 12 = 86

4. 9x = 108

x = 22

x = 25

x = 74

x = 12


Problem of the DayStephen forgot his locker number, but he remembered that the sum of the digits is 11 and that the digits are all odd numbers. The locker numbers are from 1 to 120. What is Stephen’s locker number?119


Learn to solve equations by multiplying and dividing fractions.


Dividing by a number is the same as multiplying by its reciprocal.

Remember!

5-10 Solving Fraction Equations: Multiplication and DivisionAdditional Example 1A: Solving Equations by

Multiplying and DividingSolve each equation. Write the answer in simplest form.

j = 25 35__

j ÷ = 25 ÷ 35__ 3

5__ 3

5__

j • = 25 • 35__ 5

3__ 5

3__

j = 25 • 51 • 3_____

j = 25 • 53__

j = , or 411253

___ 23__

Divide both sides of the equation by .

35__

Multiply by , the reciprocal of .

35__5

3__

5-10 Solving Fraction Equations: Multiplication and DivisionAdditional Example 1B: Solving Equations by


7x = 25__

7x1__ 2

5__ 1

7__1

7__• = •

x =

2 • 15 • 7____

x =

235__

Multiply both sides by the reciprocal of 7.

The answer is in simplest form.

5-10 Solving Fraction Equations: Multiplication and DivisionAdditional Example 1C: Solving Equations by


= 65y8__

5y8__ 6

1__ 5

8__5

8__÷ = ÷

y = , or 9 485__

Divide both sides by .

58__

5y8__ 6

1__ 8

5__8

5__• = •

35__

58Multiply by the reciprocal of .

__


Check It Out: Example 1ASolve each equation. Write the answer in simplest form.

j = 19 34__

j ÷ = 19 ÷ 34__ 3

4__ 3

4__

j • = 19 • __34__ 4

343__

j = 19 • 41 • 3_____

4j = 19 • 3__

76___ 13 j = , or 253__

Divide both sides of the equation by .

34__

Multiply by , the reciprocal of .

34__4

3__


Check It Out: Example 1BSolve each equation. Write the answer in simplest form.

3x = 17__

3x1__ 1

7__ 1

3__1

3__• = •

x =

1 • 17 • 3____

x =

121__

Multiply both sides by the reciprocal of 3.

The answer is in simplest form.


Check It Out: Example 1CSolve each equation. Write the answer in simplest form.

= 46y7__

6y7__ 4

1__ 6

7__6

7__÷ = ÷

y = , or 4 286__

Divide both sides by .

Multiply by the reciprocal of .

67__

6y7__ 4

1__ 7

6__7

6__• = •

23__

67__


Additional Example 2: Problem Solving Application

23__Dexter makes of a recipe, and he

uses 12 cups of powdered milk. How many cups of powdered milk are in the recipe?


Additional Example 2 Continued

11 Understand the Problem

The answer will be the number of cups of powdered milk in the recipe.List the important information:

23__• He makes of the recipe.

• He uses 12 cups of powdered milk.


22 Make a Plan

You can write and solve an equation. Let x represent the number of cups in the recipe.

He uses 12 cups, which is two-thirds of the amount of the recipe.

23__12 = x



Solve3323__12 = x

12 • = x •32__ 2

3__ 3

2__

121__ 3

2__• = x

6

118 = x

There are 18 cups of powdered milk in the recipe.

Multiply both sides by , the

reciprocal of .

32__

23__

Simplify. Then multiply.



Look Back44

Check 12 = x23__

23__12 =? (18)363__12 =?

12 = 12?

Substitute 18 for x.

Multiply and simplify.

18 is the solution.


121


Check It Out: Example 2

25__Nick makes of a recipe, and he

uses 8 cups of wheat flour. How many cups of wheat flour are in the recipe?


Check It Out: Example 2 Continued

11 Understand the Problem

The answer will be the number of cups of wheat flour in the recipe.

25__

List the important information:• He makes of the recipe.• He uses 8 cups of wheat flour.


22 Make a Plan

You can write and solve an equation. Let y represent the number of cups in the recipe.

He uses 8 cups, which is two-fifths of the amount of the recipe.

25__8 = y



Solve3325__ 8 = y

8 • = y •52__ 2

5__ 5

2__

81__ 5

2__• = y

4

120 = y

There are 20 cups of wheat flour in the recipe.

Multiply both sides by , the

reciprocal of .

52__

25__

Simplify. Then multiply.



Look Back44

Check 8 = y25__

25__ 8 =? (20)405__ 8 =?

8 = 8?

Substitute 20 for y.

Multiply and simplify.

20 is the solution.


81


Standard Lesson Quiz

Lesson Quizzes

Lesson Quiz for Student Response Systems


Lesson QuizSolve each equation. Write the answer in simplest form.

1. 3x = 2. x = 4

3. x = 14 4. = 9

5. Rebecca used 3 pt of paint to paint of the trim in her bedroom. How many pints will Rebecca use for the trim in the entire bedroom?

18__ 1

4__

37__ y

7__

14__

x = 16124__x =

983__ 2

3__x = or 32 y = 63

12


1. Solve the equation and identify the answer in the simplest form.

A. C.

B. D.




A. x = 5 C. x = 25

B. x = 10 D. x = 50




A. C.

B. D.




A. y = 72 C.

B. y = 17 D.



5. Lou is learning to paint pottery. He used 3 pints of paint to paint of a pot. How many pints will Lou use for the entire pot?

A. C. 3 pt

B. D. 7 pt


Warm Up Problem of the Day Lesson Presentation Lesson Quizzes.

Documents

Transcript of Warm Up Problem of the Day Lesson Presentation Lesson Quizzes.