More Percent Problems Answers
--An item costs $120. It is on sale for 25% off. You have a coupon for an additional 10% off.
What is the final sale price of the article?
120*(1-.25) = 90
90 *(1-.1) = 81
The final sale price was $81.
How much do you save overall?
120-81 = 39
You save a total of $39.
What is the overall percent savings?
(81-120)/120 = 32.5%
You save 32.5% overall.
--A retail store buys items from the manufacturer and then marks up the price 75%. During a sale, prices are discounted 25%. The store makes what percent profit?
If no original value is given, use 100.
100 * (1+.75) = 175
175 * (1-.25) = 131.25
(131.25-100)/100 = 31.25 %
--Spot prices for crude oil are rather volatile. From 1998 to 1999, spot prices for crude oil decreased by 28%. From 1999 to 2000, they increased by 106%. What was the percentage change over the two year period from 1998 to 2000?
If no original value is given, use 100.
100 *(1-.28) = 72
72 * (1+1.06) = 148.32
(148.2-100)/100 = 48.2%
The overall percent change was 48.2%
--During a 25% off sale, you buy an item for $22.50. What was the original price of the item?
For a reverse percent change use N= P * (1 + r) or N= P * (1 - r) but the original value (P) is unknown.
22.50 = P * (1-.25)
22.50 = .75 P
P = 30
The original price was $30.00.
Note: You CANNOT increase 22.50 by 25% to get the correct answer.
--In 2004, the number of new hybrid vehicle registrations was 83,153 which is an 81% increase over the previous year. How many hybrid vehicle registrations were there in 2003?
For a reverse percent change use N= P * (1 + r) or N= P * (1 - r) but the original value (P) is unknown.
83,153 = P * (1+.81)
83,153 = 1.81P
P = 45941
There were 45,941 hybrid vehicles registered in 2003.
--According to the official 2000 census, the Hispanic population of the US in 2000 was 35,306,000. The population had risen an astounding 57.9% from 1990 to 2000. What was the Hispanic population in 1990?
For a reverse percent change use N= P * (1 + r) or N= P * (1 - r) but the original value (P) is unknown.
35,306,000 = P * (1+.579)
35,306,000 = 1.579P
divide both sides by 1.579
P = 22359721
The Hispanic population in 1990 was 22,359,721.