Question

With two reapers operating, a field can be harvested in 1 h. If only the newer reaper is used, the crop can be harvested in 1.2 h. How long would it take to harvest the field using only the older reaper?

Answer 1

Answer:

The older repear will harvest in 6 hrs

Explanation:

Given a field can be harvested in 1 hr with 2 reapers

Consider the total field to be 1

Let x be the time of older’s reaper

The field can be harvested in 1.2 hr with newer reaper alone

Older’s time of harvesting = $\frac{1}{x}$ per hour

Newer’s time of harvesting = $\frac{1}{1.2}$per hour

Total (Older+Newer) = 1 = ${\frac{1}{x}+\frac{1}{1.2}$}

 $\frac{1}{x}+\frac{1}{1.2}=1$

 $\frac{1.2+x}{1.2 x}=1$

1.2 + x = 1.2x

1.2 = 0.2x

x = 6

Therefore, older repear will harvest in 6 hrs