RE-NEET 2026 Botany Growth Rate MCQ Question

To find the length of the stem at the end of the 7th day, use the formula:

$\text{Final Length} = \text{Initial Length} + (\text{Growth Rate} \times \text{Time})$

Here, the initial length is 20 cm, the growth rate is 30 cm/day, and the time is 7 days.

Calculating:

$\text{Final Length} = 20 \, \text{cm} + (30 \, \text{cm/day} \times 7 \, \text{days}) = 20 \, \text{cm} + 210 \, \text{cm} = 230 \, \text{cm}$

Thus, the length of the stem at the end of the 7th day is 230 cm, confirming option B. The other options fail because they either miscalculate the growth or do not account for the initial length correctly.