A mango kept in a basket doubles every one minute. If the basket gets completely filled by mangoes in 30 minutes then in how many minutes half of the basket was filled?

Question

Question

This question was previously asked in

NTPC CBT-I (Held On: 4 Jan 2021 Shift 1)

Answer 1

Given:

A mango kept in a basket doubles every one minute.

The basket gets filled in 30 minutes.

Calculation:

The basket is full (1) in 30 minutes.

The Time required to fill the basket with mango is 30 minutes.

So, half the basket is filled in 29 minutes.

As in every minute, the basket gets doubled. So, in 29 minutes, it is half-filled and in the next minutes, it will be completely filled.

∴ Obviously, the basket will be half-filled (1/2) filled in 29 minutes.

Alternate MethodAccording to the question,

1st min = 2¹ = 2

2nd min = 2² = 4

We have observed every min double the quantity

then in 29 min = 2²⁹ = 536870912

Last 30 min = 2³⁰ = 1073741824

We have observed the 29th min is half of the 30th min quantity.