When a partner withdraws a fixed amount at the end of every quarter, the average period for calculating interest is generally 7½ months. However, in this specific case, interest charged on Mishu's drawings amounted to ₹9,000, which reflects an average period of 4½ months instead of the usual average of 7½ months.
Step 1: Verify the given interest amount:
Interest on drawings formula: \[ \text{Interest} = \text{Total Drawings} \times \text{Rate of Interest} \times \frac{\text{Average Period}}{12}. \] Given that the total interest is ₹9,000 and the rate of interest is \(15\%\), the shorter average period of 4½ months can be confirmed based on the actual interest charged.
Conclusion:
Interest on Mishu's drawings was calculated for an average period of \(4½ \ \text{months}\).
A racing track is built around an elliptical ground whose equation is given by \[ 9x^2 + 16y^2 = 144 \] The width of the track is \(3\) m as shown. Based on the given information answer the following: 
(i) Express \(y\) as a function of \(x\) from the given equation of ellipse.
(ii) Integrate the function obtained in (i) with respect to \(x\).
(iii)(a) Find the area of the region enclosed within the elliptical ground excluding the track using integration.
OR
(iii)(b) Write the coordinates of the points \(P\) and \(Q\) where the outer edge of the track cuts \(x\)-axis and \(y\)-axis in first quadrant and find the area of triangle formed by points \(P,O,Q\).