The number of books Alisha did not sell after making a profit of £490 is 45 books
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How to find how many book she sell base on the profit?
She buys 200 books costing £3 each.
Therefore,
cost = 3 × 200 = £600
Hence,
She sells 2/5 of the books at £8 each.
total amount = 2 / 5 of 200 × 8
total amount = 80 × 8
total amount = £640
Alisha then reduces the price of the remaining books by a quarter.
She then sells some of the remaining books.
Therefore,
the remaining book = 120
She sold some of the remaining books.
profit = selling price - cost price
490 = selling price - 600
selling price = 490 + 600
selling price = £1090
Therefore,
the cost of the remaining book she sold = 1090 - 640 = £450
Hence,
let
x = number of book sold
6(x) = 450
x = 450 / 6
x = 75
The number book she did not sell = 120 - 75 = 45
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