OR In subparts (i) and (ii) choose the correct options and (ii) The Average Cost of producing ‘x’ units of in subpart (iii), answer the questions as instructed. commodity is given by:
Read the following statements and choose the (c) Find the Marginal Average Cost function.
correct option. d MC - AC
(I) The correlation coefficient and the regression
(d) Verify that ( AC ) =
dx x
coefficients are of the same sign Question 22
(II) The correlation coefficient is the arithmetic mean Two different types of books have to be stacked in
between the regression coefficients. the shelf of a library. The first type of book weighs
(III) The product of two regression coefficients is always 1 kg and has a thickness of 6 cm. The second type
equal to 1. of book weighs 1.5 kg and has a thickness of 4 cm.
(IV) Both the regression coefficients cannot be The shelf is 96 cm long and can support a maximum
numerically greater than unity. weight of 21 kg.

1. Only (IV) is correct. How should both the types of books be placed in
2. Only (I) and (II) are correct. the shelf to include the maximum number of books?
3. Only (I) and (IV) are correct. Formulate a Linear Programming Problem and solve it graphically.
4. Only (III) and (IV) are correct. 

Board paper · 2025 · Oswaal Books (reproduction of CISCE board paper)