On a certain sum the rate of C.I. is x% per annum for the first two years and y% per annum for the next three years. Then the amount after 5 years is :

1. $\Big(1 + \dfrac{x}{100}\Big)\Big(1 + \dfrac{y}{100}\Big)$ times

2. $\Big(1 + \dfrac{x}{100}\Big)^3\Big(1 + \dfrac{y}{100}\Big)^2$ times

3. $\Big(1 + \dfrac{x}{100}\Big)^2\Big(1 + \dfrac{y}{100}\Big)^3$ times

4. $\Big(1 + \dfrac{x}{100}\Big)^2\Big(1 - \dfrac{y}{100}\Big)^3$ times

The cost (₹ x) of a machine increases by 20% in the first two years and then decreases by 25% in the next two years. Then the cost of machine becomes :

1. ₹ $x \times \dfrac{120}{100} \times \dfrac{75}{100}$

2. ₹ $x \times \Big(\dfrac{120}{100}\Big)^2 \times \dfrac{75}{100}$

3. ₹ $x \times \Big(\dfrac{120}{100}\Big)^2 \times \Big(\dfrac{75}{100}\Big)^2$

4. ₹ $x \times \Big(\dfrac{80}{100}\Big)^2 \times \Big(\dfrac{75}{100}\Big)^2$

The value of an article decreased for two years at the rate of 10% per year and then in the third year it increased by 10%. Find the original value of the article, if its value at the end of 3 years is ₹ 40,095.

According to a census taken towards the end of the year 2009, the population of a rural town was found to be 64000. The census authority also found that the population of this particular town had a growth of 5% per annum. In how many years after 2009 did the population of this town reach 74088 ?