### There are five boxes in a cargo hold. The weight of the first box is 200 kg and the weight of the second box is 20% more than the weight of third box, whose weight is 25% more than the first box’s weight. The fourth box at 350 kg is 30% lighter than the fifth box. The difference in the average weight of the four heaviest boxes and the four lightest boxes is.

**A.** 37.5 kg

**B.** 51.5 kg

**C.** 75 kg

**D.** 112.5 kg

## Show Answer

###
Answer-C

Solution-

__Solution(By Apex Team)__

Weight of first box = 200 kg
Weight of third box
= 125 % of 200 kg
= 250 kg
Weight of second box
= 120% of 250 kg
= 300 kg
Weight of fourth box = 350 kg
Let the weight of fifth box be x kg
Then, 70% of x = 350 kg
$\begin{array}{l}
\Rightarrow x=\left(\Large\frac{350 \times 100}{70}\right) \\
\Rightarrow x=500 \mathrm{~kg}
\end{array}$
Average weight of four heaviest boxes
$\begin{array}{l}
=\left(\Large\frac{500+350+300+250}{4}\right) \mathrm{kg} \\
=350 \mathrm{~kg}
\end{array}$
Average weight of four lightest boxes
$\begin{array}{l}
=\left(\Large\frac{200+250+300+350}{4}\right) \mathrm{kg} \\
=275 \mathrm{~kg}
\end{array}$
$\begin{array}{l}\text{∴ Required difference}\\
\text{= (350 – 275)}\\
\text{= 75 kg}\end{array}$