Question

A watch when sold at a profit of 6% yelid 870 more than when it is sold at loss of 6 % finf the cp of the watch

Answer 1

let the cost price of the watch be ' x '

since, the watch was sold at 6 % profit

then

Find the profit :
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profit = 6 % of c.p = 6 % of x = ₹ 0.06 x

original s.p = cost price + profit

= ₹ x + ₹ 0.06 x = ₹ 1.06 x

Find the loss :
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loss = 6 % of c.p = 0.06x

new selling price = c.p - loss = x - 0.06x

= ₹0.94x

since, the yield is ₹ 870 more than the new selling price .then

Find the cost price:
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original s.p = new s.p + ₹870

1.06x = 0.94x + 870

1.06x - 0.94x = 870

0.12x = 870 => 12x ÷ 100 = 870

12x = 87000 => x = 87000 ÷ 12

x = ₹ 7250

Answer :
------------
cost price of the watch = ₹7250

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Answer 2

Difference in price = Rs 870 (Given)

Find the difference in the percentage of the selling price:

Difference in price = 6 - ( - 6) = 12%

Find the cost price:

12% = Rs 870

1% = 870 ÷ 12 = Rs 72.50

100% = 72.5 x 100 = RS 7250

Answer: The cost price of the watch is Rs 7250