Question
Harry’s expenditure and savings are in the ratio
of 9:7. If his income increases by 15% and the expenditure by 22%, then by how much percent does his savings increase?Solution
Let the saving increased by x %
(15-x)/(22-15) = 9/7 105 - 7x = 63 7x = 42 x = 6%
If the sum of the coefficients in the expansion of (a + b)n is 16384, then the greatest coefficient in the expansion is

The perimeter of a rectangular field is 34 metres and its area is 60 m2 . What is the length of the diagonal of this field?
If the sum of the coefficients of all even powers of x in the product (1 + x + x2 + … + x2n) (1 – x + x2 – x...
A certain number of books were distributed equally among a group of students in a class. Each student received a number of books equal to one-fifth of t...

Find the coefficient of x⁴ in (2x – 3/x)⁶.

Find both the maximum value and the minimum value respectively of 3a4 minus; 8a3 + 12a2 minus; 48a + 25 on the interval...