The total revenue received from the sale of \( x \) units of a product is given by \( R(x)=24x+5x^{2}+3 \). The marginal revenue when \( x=10 \) is,
Answer & explanation
Correct answer: option 2
The correct answer is Option (2) → 124
Marginal revenue is the derivative of total revenue, \( MR=\frac{dR}{dx} \):
\( \displaystyle MR=\frac{d}{dx}\left(24x+5x^{2}+3\right) \)
\( \displaystyle =24+10x \)
\( \displaystyle MR\ \text{at}\ x=10:\ 24+10(10)=124 \)
Why the other options are incorrect
Option (1) 743 — Incorrect. 743 = R(10) = 240 + 500 + 3 is the total revenue, not the marginal revenue.
Option (3) 10 — Incorrect. 10 is the given value of x; the marginal revenue there is 124.
Option (4) 155 — Incorrect. The marginal revenue at x = 10 is 124, not 155.
NCERT (2026-27 edition):
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