The price of an item is discounted 10 percent on day 1 of a sale. On day 2, the item is discounted another 10 percent, and on day 3, it is discounted an additional 20 percent. The price of the item on day 3 is what percentage of the sale price on day 1?
A. 28%
B. 40%
C. 64.8%
D. 70%
E. 72%
The OA is E.
How can I calculate this without knowing the starting price of the item? Experts, may you give me any help? Thanks in advanced.
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The price of an item is discounted 10 percent . . .
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DavidG@VeritasPrep
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You could pick an easy number to be the starting price: 100M7MBA wrote:The price of an item is discounted 10 percent on day 1 of a sale. On day 2, the item is discounted another 10 percent, and on day 3, it is discounted an additional 20 percent. The price of the item on day 3 is what percentage of the sale price on day 1?
A. 28%
B. 40%
C. 64.8%
D. 70%
E. 72%
The OA is E.
How can I calculate this without knowing the starting price of the item? Experts, may you give me any help? Thanks in advanced.
Day 1: discounted 10%. 10% of 100 is 10, so sale price = 100 - 10 = 90
Day 2 discounted 10%. 10% of 90 is 9, so new price . = 90 - 9 = 81.
Day 3: discounted 20%. 20% of 81 is 16.20. 81 - 16.20 = 64.80.
We're asked what % the price of day 3 (64.80 ) is of the sale price on day 1: (90.) 64.80/90 = 648/900 = 9 *72/9 * 100 = 72. The answer is E. [spoiler]
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DavidG@VeritasPrep
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- Posts: 2663
- Joined: Wed Jan 14, 2015 8:25 am
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Note that the algebra is virtually identical.DavidG@VeritasPrep wrote:You could pick an easy number to be the starting price: 100M7MBA wrote:The price of an item is discounted 10 percent on day 1 of a sale. On day 2, the item is discounted another 10 percent, and on day 3, it is discounted an additional 20 percent. The price of the item on day 3 is what percentage of the sale price on day 1?
A. 28%
B. 40%
C. 64.8%
D. 70%
E. 72%
The OA is E.
How can I calculate this without knowing the starting price of the item? Experts, may you give me any help? Thanks in advanced.
Day 1: discounted 10%. 10% of 100 is 10, so sale price = 100 - 10 = 90
Day 2 discounted 10%. 10% of 90 is 9, so new price . = 90 - 9 = 81.
Day 3: discounted 20%. 20% of 81 is 16.20. 81 - 16.20 = 64.80.
We're asked what % the price of day 3 (64.80 ) is of the sale price on day 1: (90.) 64.80/90 = 648/900 = 9 *72/9 * 100 = 72. The answer is E. [spoiler]
Say the starting price is P.
Day 1: discounted 10%. Sale Price = .9P
Day 2 discounted 10%. New Price . = .9*.9P = .81P
Day 3: discounted 20%. New Price = .8 * .81P = .648P
Price Day 3/Day 1 = .648P/.9P = .72P
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GMATWisdom
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let us assume sale price on day 1 after 10% discount is 100M7MBA wrote:The price of an item is discounted 10 percent on day 1 of a sale. On day 2, the item is discounted another 10 percent, and on day 3, it is discounted an additional 20 percent. The price of the item on day 3 is what percentage of the sale price on day 1?
A. 28%
B. 40%
C. 64.8%
D. 70%
E. 72%
The OA is E.
How can I calculate this without knowing the starting price of the item? Experts, may you give me any help? Thanks in advanced.
then sale price on day 2 would be = 100- 10= 90 (10% of 100 is 10)
and the sale price on day3 would be = 90 - 18 = 72 (20% of 90 is 18)
hence the sale price of day3 as compared to sale price of day1 is = 72%
therefore D is the correct option.
