Quantities $r$ and $s$ vary inversely. When $r$ is $1200,$ $s$ is $0.35.$ What is the value of $s$ when $r$ is $2400$?

0.175

Explanation:

Data provided in the question:

r and s vary inversely

Mathematically, we can represent the relation as

rs ∝ 1

or

rs = k ... (i)

here,

k is the proportionality constant

when,

r = 1200; s = 0.35

thus,

1200 * 0.35 = k

or

k = 420 ... (ii)

similarly for case when r = 2400

rs = k [ From (i) ]

2400s = 420 [ value of k from (ii) ]

or

s = 0.175