1. Original price-- $80
Percent of discount—20%
Sale price-- ???
Convert 20% to a decimal by dividing by 100, = 0.20 Multiply that by $80
80 x 0.20 = $16 discount.
80 - 16 = $64 sale price
Or you can say after you take 20% away, you have 80% left. Multiply $80 x 0.80 = $64
2.Original price-- $82
Percent of discount-- ???
Sale price-- $65.60
Full price x percent left after discount = sale price
82x = 65.60 divide both sides by 82
x = 0.8
Multiply that times 100 to get the percentage,
x = 80%
3. Original price-- ???
Percent of discount—5%
Sale price-- $57
5% off leaves us 95% to pay = 0.95
0.95x = 57
x = $60
4.A store pays $85 for a game system. They mark it up 125%. If 6% sales tax is applied on top of the new price, what is the final price of the aquarium?
85 x 1.25 = 106.25
106.25 x 0.06 = 6.375 added
106.25 + 6.375 = 112.625 = $112.63
5. Your friend used a $20 coupon to purchase a pair of sneakers that were advertised at $139.99. You buy the same shoes, but you use a 20% off coupon. Who paid a cheaper price?
Remember that 20% off = paying 80%
139.99 - 20 = $119.99
139.99 x 0.8 = $111.99
You pay a cheaper price
6. A store buys an item for $10. To earn a profit of $25, what percent does the store need to markup the item?
$10 cost + $25 profit = $35 new price
So we need percent difference between 10 and 35
10x = 35
x = 3.5, multiply by 100 to get the percentage = 350%
7.You and 2 friends go out to dinner. The food bill comes to $35.20, and you are charged an additional 6% sales tax. You then want to leave an 18% tip just on the price of the food. If you split the final amount evenly, how much should each person pay?
Well, we can ignore the tax part and look at the price of the food + price of the food x 18%
35.20 x 1.18 = 41.536
41.54 divided by 3 people = $13.85 per person
8.You start the baseball season with 10 strikeouts. By the end of the season, you only have 4 strikeouts. What is the percent of change of the number of strikeouts? (don’t forget increase or decrease!)
10x = 4
x = 0.4 = 40% decrease.
LMK if you have questions about these
