Some equations have been solved on the basis of a particular system. On the same basis, find the correct answer to the equation.
1 × 3 × 5= 531
2 × 7 ×9 =972
4 × 6 × 8=?

The equation will be corrected by converting which two symbols?
19 + 63 ÷  7 – 8 × 12= 79

6 years ago, Raju's age was 2 years less than half of his brother's age, which was 20 years. What is his present age?

If '+' becomes '-' and '×' becomes '÷', find the value of ((175 + 160) × 50) × 10.

Select the group that has the same relation between the given numbers as the relation between the following group numbers.
(4, 9, 37)

If the ink of one pan ends up writing 10 page, how many panes will be required to write 20 copies of 40 page?

Which two numbers have to be interchanged to correct the given equation?
55 + 32 – 4 × ( 1 × 12 ) + ( 16 ÷ 4 ) =31

The average age of three friends A, B, C is 20 years. The average age of A and B is 19 years, then what is the age of C?