Given: Total cost = ₹ 15,000
Direct material = ₹ 5,000
Factory overhead is 150% of direct labour cost.
Let direct labour cost be ₹ X.
Then, factory overhead = 150% of X = 1.5X.
Total cost = Direct Material + Direct Labour + Factory Overhead
So, ₹ 15,000 = ₹ 5,000 + X + 1.5X
Combine terms: ₹ 15,000 = ₹ 5,000 + 2.5X
So, 2.5X = ₹ 10,000
Therefore, X = ₹ 4,000
Oops! But this suggests ₹ 4,000 — wait! Let’s double-check:
₹ 5,000 (Material) + X (Labour) + 1.5X (Overhead) = 15,000
So: 5,000 + 2.5X = 15,000 → 2.5X = 10,000 → X = 4,000
So the amount of direct labour charged is ₹ 4,000 — therefore the correct answer is (B) ₹ 4,000.
(Note: The original options show ₹ 4,000 as (B), so we choose that.)
Correct Answer: (B) ₹ 4,000

A ladder of fixed length \( h \) is to be placed along the wall such that it is free to move along the height of the wall.
Based upon the above information, answer the following questions:
(iii) (b) If the foot of the ladder, whose length is 5 m, is being pulled towards the wall such that the rate of decrease of distance \( y \) is \( 2 \, \text{m/s} \), then at what rate is the height on the wall \( x \) increasing when the foot of the ladder is 3 m away from the wall?