Respuesta :
Cost of the books = £3 x 30 = £90
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Sales from 3/5 of the books :
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3/5 of the books = 3/5 x 30 = 18
40% of £3 = 0.4 x £3 = £1.20
Selling Price = £3 + £1.20 = £4.20
Total Sales = £4.20 x 18 = £75.60
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Sales from the remaining books :
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Remaining books = 30 - 18 = 12
Selling Price = £4.20 - 20% x £4.20
Selling Price = £4.20 - 0.2 x 4.20
Selling Price = £3.36
Sales = £3.36 x 12 = £40.32
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Find Percentage Profit :
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Total Sales = £75.60 + £40.32 = £115.92
Profit = £115.92 - £90 = £25.92
Percentage Profit = 25.92/90 x 100 = 28.8%
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Answer: 28.8%
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----------------------------------------------------------------------------
Sales from 3/5 of the books :
----------------------------------------------------------------------------
3/5 of the books = 3/5 x 30 = 18
40% of £3 = 0.4 x £3 = £1.20
Selling Price = £3 + £1.20 = £4.20
Total Sales = £4.20 x 18 = £75.60
----------------------------------------------------------------------------
Sales from the remaining books :
----------------------------------------------------------------------------
Remaining books = 30 - 18 = 12
Selling Price = £4.20 - 20% x £4.20
Selling Price = £4.20 - 0.2 x 4.20
Selling Price = £3.36
Sales = £3.36 x 12 = £40.32
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Find Percentage Profit :
----------------------------------------------------------------------------
Total Sales = £75.60 + £40.32 = £115.92
Profit = £115.92 - £90 = £25.92
Percentage Profit = 25.92/90 x 100 = 28.8%
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Answer: 28.8%
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