In 4 years, an amount of ₹ 6,000 becomes ₹ 8,000 at a certain rate of simple interest. In what time at the same simple interest rate, will an amount of ₹ 525 become ₹ 700?

According to question,

In 4 years, an amount of ₹ 6,000 becomes ₹ 8,000 at a certain rate of simple interest.

So, simple interest = ₹ (8,000-6,000) = ₹ 2,000

Now, S.I. = P*r*t/100

so, $$2000=\frac{6000\times\ r\times\ 4}{100}$$

or, r= $$\frac{50}{6}$$%

Now, in second case, simple interest = $$700-525=175$$

So, $$175=525\times\ \frac{50}{6}\times\ \frac{t}{100}$$

or, $$t=175\times\ \frac{12}{525}=4$$

So, time = 4 years