Question
Aarav bought a device for Rs. 2800 and spent some money
on installation. He marked up the price by 25%, gave a Rs. 320 discount, and still earned a 15% profit. Find the installation cost.Solution
Let installation cost = Rs. x
Effective cost = 2800 + x
Marked Price = 1.25(2800 + x)
Selling Price = Marked – 320 = 1.15(2800 + x)
1.25(2800 + x) – 1.15(2800 + x) = 320
0.10(2800 + x) = 320
2800 + x = 3200
x = Rs. 400
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