What approximate value should come in place of the question mark (?) in the following questions? (You are not expected to calculate the exact value.) 7428 $\div$346 $\times$ 12 = ?

What approximate value should come in place of the question mark (?) in the following questions? (You are not expected to calculate the exact value.) 15.2% of 725$\times$12.8% of 643 = ?

What approximate value should come in place of the question mark (?) in the following questions? (You are not expected to calculate the exact value.) (36.14) $^2$ -(21.28)$^2$ = ?

What approximate value should come in place of the question mark (?) in the following questions? (You are not expected to calculate the exact value.) $\sqrt[3]{769}$ $\times$ $\sqrt {478}$ = ?

What approximate value should come in place of the question mark (?) in the following questions? (You are not expected to calculate the exact value.) 496 $\div$ 0.6$\times$0.5 = ?

The water in a rectangular reservoir having a base 80m x 60m is 6.5m deep. In what time can the water be emptied by a pipe of which the cross-section is a square of side 20cm, if the water runs through the pipe at the rate of 15kmph?

A man whose bowling average is 12.4 takes 5 wickets for 26 runs and thereby decreases his average by 0.4. Find the number of wickets taken by him before his last match

A and B started a partnership business investing some amount in the ratio of 3 : 5. C joined then after six months with an amount equal to that of B. In what proportion should the profit be at the end of one year be distributed among A, B and C?