Q24 / 180 · NEET 2026 (Re-NEET) · Botany
Length of the stem at time 0 is $20$ cm. The arithmetic growth rate is $30$ cm per day. What is the length of the stem at the end of the $7^{th}$ day ?
- A$460$ cm
- B$50$ cm
- C$170$ cm
- Correct answerD$230$ cm
Solution
The equation for arithmetic growth is given by:
$L_t = L_0 + rt$
Where:
$L_t$ is the length at time $t$
$L_0$ is the initial length at time $t = 0$
$r$ is the arithmetic growth rate
$t$ is the time
Given:
$L_0 = 20$ cm
$r = 30$ cm/day
$t = 7$ days
Substituting the given values into the equation:
$L_7 = 20 + 30 \times 7$
$L_7 = 20 + 210$
$L_7 = 230$ cm
$L_t = L_0 + rt$
Where:
$L_t$ is the length at time $t$
$L_0$ is the initial length at time $t = 0$
$r$ is the arithmetic growth rate
$t$ is the time
Given:
$L_0 = 20$ cm
$r = 30$ cm/day
$t = 7$ days
Substituting the given values into the equation:
$L_7 = 20 + 30 \times 7$
$L_7 = 20 + 210$
$L_7 = 230$ cm
Hence, the correct answer is option: 'D'.