Explanation:

Let’s break it down.

- Ram puts in ?8000 at R% for 2 years.

? If it’s simple interest:

Interest = (8000 × R × 2) / 100

So, Interest1 = 160R

Amount after 2 years = 8000 + 160R

- Now, he throws that total amount into scheme B at 12.5% for a year.

Interest2 = (8000 + 160R) × 12.5 / 100 = 1000 + 20R

- Add up the interests:

Total interest = Interest1 + Interest2

So, 160R + 1000 + 20R = 3700

? 180R = 2700

? R = 15

- So, the right option is Option 1: 15%

Option review:

- Option 1 (15%) — That’s correct

- Option 2 (12%) — Too low

- Option 3 (10%) — Also not enough

- Option 4 (18%) — Overshoots

- Option 5 (None of these) — Not needed