Over a three-week period, the price of an ounce of gold increased by 25% in the first week, decreased by 20% in the following week, and increased by 5% in the third week. If the price of gold was G dollars per ounce at the beginning of the three weeks, what was the price, in terms of G, at the end of the three weeks?
A. 0.95G
B. G
C. 1.05G
D. 1.1G
E. 1.15G
The OA is C.
Please, can anyone explain this PS question for me? I tried to solve it but I can't get the correct answer. I need your help. Thanks.
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Over a three-week period, the price of an ounce of gold
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Let G = 100.swerve wrote:Over a three-week period, the price of an ounce of gold increased by 25% in the first week, decreased by 20% in the following week, and increased by 5% in the third week. If the price of gold was G dollars per ounce at the beginning of the three weeks, what was the price, in terms of G, at the end of the three weeks?
A. 0.95G
B. G
C. 1.05G
D. 1.1G
E. 1.15G
After a 25% increase, the price = 100 + (25/100)(100) = 100 + 25 = 125.
After a 20% decrease, the price = 125 - (20/100)(125) = 125 - 25 = 100.
After a 5% increase, the price = 100 + (5/100)(100) = 100 + 5 = 105.
The question stem asks for the final price: 105.
Now plug G=100 into the answer choices to see which yields a final price of $105.
Only C works:
(1.05)G = (1.05)(100) = 105.
The correct answer is C.
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The price of gold at the end of the 3 weeks was:swerve wrote:Over a three-week period, the price of an ounce of gold increased by 25% in the first week, decreased by 20% in the following week, and increased by 5% in the third week. If the price of gold was G dollars per ounce at the beginning of the three weeks, what was the price, in terms of G, at the end of the three weeks?
A. 0.95G
B. G
C. 1.05G
D. 1.1G
E. 1.15G
G x 1.25 x 0.8 x 1.05 = 1.05G = 1.05G
Answer: C
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