Question

please answer the question please​

Answer 1

Let the amount received by Vivek = $x$

Amount received by Vaibhav = $y$

Then amount received by Rishi = $23790-(x+y)$

Interest = $5$% per year

Amount of Vivek after 2 years = $x+2*\frac{5}{100}x$

i.e., amount of Vivek = $\frac{110x}{100}$

Amount of Vaibhav after 3 years = $y+3*\frac{5}{100} y$

i.e., amount of Vaibhav = $\frac{115y}{100}$

Amount of Rishi after 4 years = $23790-(x+y) + 4*\frac{5}{100}[23790-(x+y)]$

i.e., amount of Rishi = $\frac{120(23790-x-y)}{100}$

Given

All these amouts are equal

Hence

$\frac{110x}{100}=\frac{115y}{100}$

$110x=115y$

$22x=23y$

$\frac{110x}{100}=\frac{120(23790-x-y)}{100}$

$110x = 120*23790 - 120x-120y$

$230x+120y = 2854800$

$23x+12y=285480$

Multiplying by $\frac{22}{23}$ throughout

$22x+\frac{264}{23}y = \frac{285480*22}{23}$

But we have $22x=23y$

So,

$23y + \frac{264}{23} y = \frac{285480*22}{23}$

$529y+264y = 285480*22$

$793y = 285480*22$

$y = 360*22$

$y = 7920$

That is, amount received by Vaibhav = Rs 7920

Hence option D is correct

HOPE IT HELPS !!