Question

A primary root grows from 5 cm to 19 cm in a week. The absolute growth rate is ________ and the relative growth rate is _______ respectively, over a period of one week.

• A. 2/day and 2.8
• B. 2/day and 2
• C. 28/day and 28
• D. 28/day and 4

Answer 1

The correct option is A

2/day and 2.8

Absolute growth rate is the total growth per unit time. Relative growth rate is the increase in growth of a system with respect to initial parameter during a constant period of time.

Total growth rate in a week (7-days) = 19-5 = 14 cm.

Absolute growth per day =$\frac{Totalgrowthrate}{Numberofdays}$= $\frac{14}{7}$ = 2.0/day.

Relative growth rate = $\frac{\mathrm{Total}\mathrm{growth}\mathrm{rate}}{\mathrm{Initial}\mathrm{growth}\mathrm{rate}}$= $\frac{14}{5}$ = 2.8.