The average marks of the students of a class is 68. The average marks of girls in the class is 80 and that of boys is 60. What percentage of students are boys in the class?

If 15% of 40 is 2 more than 25% of a number, then the number will be

A car covers the first 35 km in 45 minutes and the remaining 69 km in 75 minutes. What is the average speed of the car?

What will be the compound interest of Rs 160000 payable half yearly at 10% per annum in 2 years?

What will be the difference between the compound interest and the simple interest on a sum of 1000 for 2 years at 5% per annum?

The side of a trapezium pyramid with a square base is 24 cm. and its height is 5 cm. What will be the area of its oblique surface in cm²?

What will be the compound interest on Rs 10000 for 3 years when the rate of interest is 4% in the first year, 5% in the second year and 6% in the third year?

The average score of 14 students was calculated as 71. But later it was found that marks of one student were recorded as 42 instead of 56 and as 74 instead of 32 of the other. Correct average?