Question

Amala is twice as good as Kesha in making a chart and together they finish the chart in 16 days. Find the number of days taken by Amala alone to finish the chart.

1. 18 days
2. 20 days
3. 24 days
4. 22 days
5. 25 days

Answer 1

Correct Answer - Option 3 : 24 days

Given:

The efficiency of Amala = 2 × efficiency of Kesha

Time taken by Amala and Kesha together to finish the chart = 16 days

Formula Used:

Efficiency = (Total work)/(Time taken)

Calculation:

(Efficiency of Amala)/(Efficiency of Kesha) = 2/1

Then, (Time taken by Amala)/(Time taken by Kesha) = 1/2

Let the time taken by Amala and Kesha be x days and 2x days respectively.

Total work = LCM of x and 2x

⇒ 2x units

Then, total efficiency of Amala and Kesha together = 2 + 1

⇒ 3 units

Time taken by Amala and Kesha together = (2x/3) days

According to the question,

2x/3 = 16

⇒ 2x = 3 × 16

⇒ x = 24

∴ Amala alone can finish the chart in 24 days.