IIM Kozhikode (QA) PYQs

One country's GDP is currently $600 billion and is growing at 10% per annum. Another country's GDP is $700 billion, while it is growing at 5% per annum. How many years will it take for the GDP of the 1st country to overtake the 2nd?

A factory kept increasing its output by the same percentage every year. Find the percentage if it is known that the output has doubled in the last two years. (assume $\sqrt{2} = 1.4142$)

$8\%$ of boys in a class made it past the 90th percentile, while $12\%$ of the girls in the same class made it past that mark. Suppose there are $120$ students in this class: what is the number of boys?