Usha and Mohak were partners in a firm. Usha withdrew a fixed amount at the end of every half-year for the year ended 31st March, 2024. Interest on drawings is charged at 9% p.a. Interest on Usha’s drawings will be charged for months.
Step 1: Usha withdrew a fixed amount at the end of every half-year. That means she withdrew twice in the year:
- First withdrawal at the end of September 2023
- Second withdrawal at the end of March 2024
Step 2: Interest on drawings is calculated for the period from date of withdrawal till the end of the financial year.
Step 3: Interest is charged as follows:
- For withdrawal on 30th September, interest = 6 months (Oct to Mar)
- For withdrawal on 31st March, interest = 0 months
Step 4: Average period = \( \frac{6 + 0}{2} = 3 \) months
Interest on drawings will be charged for 3 months.

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?