A papaya tree was planted 2 years ago. It grows at the rate of 20\% every year. If at present, the height of the tree is 540 cm, what was it when the tree was planted?
(a)324 cm
(b)375 cm
(c)400 cm
(d)432 cm
Answer
Answer (as printed): B
Explanation
Height of the tree 2 years ago $=\frac{540}{\left(1+\frac{20}{100}\right)^{2}} \mathrm{cm}$ $$=\left(540 \times \frac{5}{6} \times \frac{5}{6}\right) \mathrm{cm}=375 \mathrm{cm} .$$