Question

The present price of a T.V. is ₹ 72900. If its value decreases 10% every year then what was its value 2 years ago?

Answer 1

Given:

• Present price of the T.V., (V₀ = ₹ 72900).
• The value decreases 10% every year.
• We need to find the value 2 years ago.

Step-wise calculation:

Since the value decreases by 10% per year, the T.V. value each year retains 90% of the previous year’s value.

Let the value 2 years ago be (V).

The relation between present value and the value 2 years ago is:

V₀ = V × (1 – 0.10)²

V₀ = V × (0.90)²

V₀ = V × 0.81

Therefore,

`V = V_0/0.81`

`V = 72900/0.81`

V = ₹ 90000

The value of the T.V. 2 years ago was ₹ 90000.