Transparency 7 Click the mouse button or press the Space Bar to display the answers.
Example 7-4c Objective Find and use the percent of increase or decrease
Example 7-4c Vocabulary Percent of change A ratio that compares the change in a quantity to the original amount
Example 7-4c Vocabulary Percent of increase The percent of change when the new number is greater than the original
Example 7-4c Vocabulary Percent of decrease The percent of change when the new number is less than the original
Example 7-4c Vocabulary Markup The amount the price of an item is increased above the price the store paid for the item
Example 7-4c Vocabulary Selling price The amount the customer pays for an item
Example 7-4c Vocabulary Discount The amount by which a regular price is reduced
Lesson 7 Contents Example 1Find the Percent of Increase Example 2Find the Percent of Change Example 3Find the Selling Price Example 4Find the Sale Price
Example 7-1a HOMES The Nietos bought a house several years ago for $120,000. This year, they sold it for $150,000. Find the percent of increase. 1/4 Write formula for percent of change % of change = Amount of change Original amount Remember: amount of change is final - start % of change = 150,000 - Sold is “final” Bought is “start” 150, ,000 Start is the original 120,000
Example 7-1a HOMES The Nietos bought a house several years ago for $120,000. This year, they sold it for $150,000. Find the percent of increase. 1/4 Follow order of operations % of change = Amount of change Original amount % of change = 150, , , ,000 Subtract numerator % of change = 30,000 Bring down denominator 120,000 Divide numerator by denominator % of change =0.25 Multiply by 100 and add % sign % of change =25% Answer:
Example 7-1c CLUBS Last year Cedar Park Swim Club had 340 members. This year they have 391 members. Find the percent of increase. Answer: % of change = 15% 1/4
Example 7-2a SCHOOLS Johnson Middle School had 240 students last year. This year, there are 192 students. Find the percent of change. State whether the percent of change is an increase or a decrease. 2/4 Write formula for percent of change % of change = Amount of change Original amount % of change = This year is “final” Last year is “start” Last year is original 240 Follow order of operations Subtract numerator % of change = - 48
Example 7-2a SCHOOLS Johnson Middle School had 240 students last year. This year, there are 192 students. Find the percent of change. State whether the percent of change is an increase or a decrease. 2/4 Bring down denominator % of change = Amount of change Original amount % of change = % of change = Divide numerator by denominator % of change = Multiply by 100 and add % sign % of change = -20% Negative % indicates decrease % of change = -20% ; decrease Answer:
Example 7-2c CARS Meagan bought a new car several years ago for $14,000. This year she sold the car for $9,100. Find the percent of change. State whether the percent of change is an increase or a decrease. Answer: % of change = 35%; decrease 2/4
Example 7-3a MARKUP Shirts bought by a sporting goods store cost them $20 per shirt. They want to mark them up 40 percent. What will be the selling price? Mark-up means to add the % to the original 3/4 Write problem The original price of the shirt is $20 Selling price = 20 Add the mark-up % % Do NOT convert % to decimal
Example 7-3a MARKUP Shirts bought by a sporting goods store cost them $20 per shirt. They want to mark them up 40 percent. What will be the selling price? Use calculator to solve 3/4 Selling price = % Enter Enter addition sign + + Enter Enter % % Enter = = Selling price = 28 Add dimensional analysis Selling price = $28 Answer:
Example 7-3b MARKUP Silk flowers bought by a craft store cost them $10 per yard. They want to mark them up 35 percent. What will be the selling price? Answer: Selling price = $ /4
Example 7-4a SHOPPING A computer usually sells for $1,200. This week it is on sale for 30% off. What is the sale price? 4/4 Sale price means to subtract the % from the original Write problem Sale price = 1,200 The original price of the computer is $1,200 Subtract the sale % Sale price = 1, % Do NOT convert % to decimal
1, Example 7-4a SHOPPING A computer usually sells for $1,200. This week it is on sale for 30% off. What is the sale price? 4/4 Sale price = 1,200 Sale price = 1, % Use calculator to solve Enter 1,200 1,200 Enter subtraction sign - - Enter 30 Enter % % Enter = = Sale price = 840 Add dimensional analysis Sale price = $840 Answer:
Example 7-4c SHOPPING A DVD sells for $28. This week it is on sale for 20% off. What is the sale price? Answer: Sale price = $22.40 * 4/4