A tree increases annually by 1⁄5 th of its height. If its height today is 50 cm, what will be the height after 2 years?
Choose the most appropriate option.
A) 64 cm  B) 84 cm  C) 72 cm  D) 64 cm  E) 74 cm
Explanation:   This problem is similar to the problems we saw in compound interest.   We can use the formulas of compound interest here as well.   Rate of increase = 1/5 × 100 = 20%   Height after 2 years = P(1+R/100)T   = 50(1 + 20/100)2 = 50(1 + 1/5)2   = 50(6/5)2 = (50 × 6 × 6)/(5 × 5) = 2 × 6 × 6 = 72 cm   Answer: Option 72 cm
<result>C</result>
A tree increases annually by 1⁄5 th of its height. If its height today is 50 cm, what will be the height after 2 years?