The ingredients in the recipe will make 4 servings of frozen yogurt. Determine the following: If you want to make 8 servings, what would you do to the.

BELL WORKThe ingredients in the recipe will make 4

servings of frozen yogurt. Determine the following:

If you want to make 8 servings, what would you do to the amounts for each ingredient?

What would you do to make 2 servings?Suppose you wanted 6 servings. How much

more is six than four?2 cups milk¾ cup honey1 dash salt2 eggs, beaten

2 cups plain yogurt1 tablespoon Vanilla

OBJECTIVE: REVIEW USE OF RATIOS, PROPORTIONS, PERCENTAGES AND PERCENT CHANGE

2.6 Ratios and ProportionsRatios and Proportions

CFU3102.3.14; Solve absolute value equations and inequalities (including compound inequalities) with one variable and graph their solutions on a number line. SPI 3102.3.5 ; Write and/or solve linear equations, inequalities, and compound inequalities including those containing absolute value.

2.7 Percent of Change

CFU3102.1.5; formulas, equations, and inequalities to solve real-world problems including time/rate/distance, percent increase/decrease, ratio/proportion, and mixture problems.;

CFU3102.1.8 Recognize and perform multiple steps in problem solving when necessary.

BRAIN POP VIDEO

http://www.glencoe.com/sec/math/brainpops/00112047/00112047.html

RATIOS Ratio is a comparison between two

numbers x to y x:y x/y

An equation stating that two ratios are equal is called a Proportion

= =Two ratios are proportional

USE CROSS PRODUCT

If cross product of ratios are equal, the ratios are proportionate

If then =

EXAMPLE 2Cross Products

A. Use cross products to determine whether the pair of ratios below forms a proportion.

Original proportion

Answer: The cross products are not equal, so the ratios do not form a proportion.

Find the cross products.

Simplify.

?

?

SOLVE FOR VARIABLE IN RATIO

EXAMPLE 3Solve a Proportion

Original proportion

Find the cross products.

Simplify.

Subtract 16 from each side.

Answer: x = 5 Divide each side by 4.

B.

PERCENT OF CHANGE

A. Determine whether the percent of change is a percent of increase or a percent of decrease. Then find the percent of change.

original: 32new: 40

Find the amount of change. Since the new amount is greater than the original, the percent of change is a percent of increase.

40 – 32 = 8

PERCENT OF CHANGE

Find the percent using the original number, 32, as the base.

Answer: The percent of increase is 25%.

change

original amount

percent of change

100 percent

8(100) = 32(r) Find the cross products.

800 = 32r Simplify.Divide each side by

32.

25 = r Simplify.

SOLVE THE FOLLOWING Change from 20 to 4

The price a used book store pays to buy a book is $5. The store sells the book for 28% above the price that is pays for the book. What is the selling price of the $5 book?

EXAMPLE 1B

A. increase of 300%

B. decrease of 300%

C. increase of 25%

D. decrease of 25%

B. Determine whether the percent of change is a percent of increase or a percent of decrease. Then find the percent of change.

original: 12new: 48

EXAMPLE 3Sales Tax

SALES TAX A meal for two at a restaurant costs $32.75. If the sales tax is 5%, what is the total price of the meal?

Step 1 Find the tax.

The tax is 5% of the price of the meal.

5% of $32.75 = 0.05 × 32.75 5% = 0.05

= 1.6375 Use a calculator.

EXAMPLE 3Sales Tax

Step 2 Find the cost with tax.

Round $1.6375 to $1.64. Add this amount to the original price.

$32.75 + $1.64 = $34.39

Answer: The total price of the meal is $34.39.

EXAMPLE 4Discounts

DISCOUNT A dog toy is on sale for 20% off the original price. If the original price of the toy is $3.80, what is the discounted price?Step 1 Find the discount.

The discount is 20% of the original price.

20% of $3.80 = 0.20 × 3.80 20% = 0.20

= 0.76 Use a calculator.

EXAMPLE 4Discounts

Step 2 Find the cost after discount.

Subtract $0.76 from the original price.

$3.80 – $0.76 = $3.04

Answer: The discounted price of the dog toy is $3.04.

PRACTICE ASSIGNMENT

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