Answer: 681.82 pounds
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Step-by-step explanation:
If a price decreases by 12%, then you pay the remaining 88%. Notice how 88% + 12% = 100%
If x is the original price before the discount, then 0.88x represents the price after the discount, which is 600 pounds.
0.88x = 600
x = 600/0.88
x = 681.818 approximately
x = 681.82 pounds
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Another way to look at it.
x = original price before discount
12% of x = 0.12x = amount you save
x - 0.12x = (1-0.12)x = 0.88x = final price after discount = 600
The steps afterward are the same as above.
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If the original price is £681.82, and the discount is 12%, then you save 0.12*681.82 = 81.8184 = 81.82 pounds. So the final price is 681.82 - 81.82 = 600 pounds which verifies the answer.