Question

the cost of a machinery depreciated every year at a uniform rate of 10% the cost of an old machinery at present is rupees 72900.three years ago it cost was:​

Answer 1

Hey mate,...  

The value of the machine an year ago=x.  It's 10% will be x*10%=x/10

If we analyze the question we can say that  

A=p(1-R/100)ⁿ

 72900=p(1-10/100)³  

72900=p=9³/10³

72900/p=(9³/10³)  

p=72900×1000    

--------------------      

729  

p=100×1000

 p=100000

Hope it will help you.

Answer 2

SOLUTION:-

(Rs. 1,00,000)

Steps to follow:-

Here,

The current cost= Amount = Rs. 72900

Rate = 10%.

Time= 3 Years .

Let the Cost of the machinery before three years from now be P .

As it is a case of depreciation:

We will use the formula

A= P× (1-R/100)^n

The further steps to solve is shown in the attachment: