a : b = 5 : 8 and b : c = 2 : 6. If a = 25, then find the value of c.

A typist takes 40 minutes to type 2 pages. How long (in minutes) will he take to type 110 pages?

The cost of 40 packets of 12 pens is ₹1680. The cost of 30 packets each containing 9 pens is

If x varies directly to y and if x = 3, y = 5, then find the value of y when x = 7.8.

The rate of advertisement on a TV channel is directly proportional to the duration of the advertisement. If the rate of an advertisement of 20 seconds is Rs. 1,25,000, then the rate of an advertisement of 25 seconds will be Rs. ________.

x varies inversely to the square of y. Given that y = 5 when x = 6, find the value of x when y = 4.

If B₁, B₂ and B₃ are three kinds of birds on a tree in the ratio 3 : 7 : 5 and the number of B₂ birds are more than B₁ birds by a multiple of 9 and 7 both, then the minimum number of birds on the tree are -

If x and y are inversely proportional, then which of the following is correct?

What will come in place of ‘A’ in the given equation?
​$$\frac{A}{192} = \frac{48}{A}$$​​

If x varies indirectly to y² and if x = 78, y = 11, then find the value of x when y = 2.2