Question

A shopkeeper earned a profit of 5 %by selling a television for ₹8500. Find the cost of price of the television.

Answer 1

Selling price of TV = ₹8500

Profit = 5%

Cost price = ?

We know that

$percent \: profit = \frac{sp - cp}{cp} \times 100 \\ \\ \Rightarrow 5 = \frac{8500 - cp}{cp} \times 100$

$\Rightarrow cp = \frac{(8500 - cp) \times 100}{5} \\ \\ \Rightarrow cp = 20(8500 - cp)$

$\Rightarrow cp = 20 \times 8500 -20 cp \\ \\ \Rightarrow 21cp = 170000 \\ \\ \Rightarrow cp = \frac{170000}{21}$
$\Rightarrow cp =8095.24$

Cost price is ₹8095.23

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Easy way:

profit = 5%

SP = ₹8500

CP = [SP/(100+Profit)] × 100

=> CP = 8500/105 × 100

=> CP = ₹8095.25