Question

A trader purchases a watch and a wall clock for rs 390. he sells them making a profit of 10%on the watch and 15%on the wall clock. he earns a profit of rs 51.50. the difference between the original prices of the wall clock and the watch is equal to

Answer 1

after calculating the difference of rate should be rs 110

Answer 2

Answer:

The difference between the original prices of the wall clock and the watch is Rs.110.            

Step-by-step explanation:

Given : A trader purchases a watch and a wall clock for Rs.390. He sells them making a profit of 10%on the watch and 15%on the wall clock. He earns a profit of Rs.51.50.

To find : The difference between the original prices of the wall clock and the watch is equal to ?

Solution :

A trader purchases a watch and a wall clock for Rs.390.

Let the cost price of the watch be Rs.x.

The cost price of the wall clock be Rs.390-x.

Total profit = Rs.51.50

He sells them making a profit of 10%on the watch.

Profit on watch is

$P_1=\frac{10x}{100}$

He sells them making a profit of  15%on the wall clock.

Profit on wall clock is

$P_2=\frac{15(390-x)}{100}$

According to question,

$P_1+P_2=51.50$

$\frac{10x}{100}+\frac{15(390-x)}{100}=51.50$

$10x+15(390-x)=5150$

$10x+5850-15x=5150$

$5x=700$

$x=\frac{700}{5}$

$x=140$

The cost price of the watch is x=Rs.140.

The cost price of the wall clock is 390-x=390-140=Rs.250.

The difference between the original prices of the wall clock and the watch is 250-140=Rs.110.