Question

If a and b vary inversely to other, then find the values of p, q, r ; x, y, z and l, m, n.

a	l	9	n	6
b	5	m	25	10

Answer 1

If a and b vary inversely to other.

i.e. ab = k  ...(Constant)

For table,

a	l	9	n	6
b	5	m	25	10

If a = 6 and b = 1

Then, a × b = 6 × 10 = 60

⇒ k = 60

When a = l and b = 5, then

ab = k

⇒ l × 5 = 60

⇒ p = `60/5` = 12

When a = 9 and b = m, then

ab = k

∴ 9 × m = 60

⇒ m = `60/9 = 20/3`

When a = n and b = 25, then

ab = k

⇒ n × 25 = 60

⇒ r = `60/25 = 12/5`