Question

. A machine is depreciated in such a way that the value of the machine at the end of any year is
90% of its value at the beginning of the year. The cost of the machine was 12000 and it was
sold eventually as waste metal for 200. Find the number of years during which the machine
was in use​

Answer 1

Step-by-step explanation:

Let the required number of years = n years

∴ Value of machine after n years = Its value when new (1−

100

r

)

n

⇒Rs.128000=Rs.250000(1−

100

20

)

n

⇒

Rs.250000

Rs.128000

=(

100

80

)

n

=(

5

4

)

n

On simplifying, we get :

(

5

4

)

3

=(

5

4

)

n

⇒n=3years