Question

if r varies inversely as s and r = 100 when s = 27, find the value of r when s = 45.​

Answer 1

Answer:

r varies inversely as s

so, r=k/s where k is constant

=> rs=k

r=100 when s=27

so,

k=r×s=27×100=2700

when s=45 then

r=k/s=2700/45=60

the value of r=60

Answer 2

Given: r=100 when s=27

To find The value of r when s = 45.​

Solution: For a particular occurrence, when one thing increases and the other thing decreases, as a result, there is a phenomenon of contrasting process, this is said to be inversely proportional.

Now taking a constant let c, then as r varies inversely as s, we have

r×s=c  [to obey the inverse proportion condition we take a constant 'c']

⇒c= 100×27  [substituting the values of r=100 and s=27]

⇒ c=2700

Again for the second case to find the value of r when s=45, c will be 2700 as it is a constant.

So, we can write

r×s=c

⇒r=c/s

⇒r=2700/45   [substituting the values of c=2700 and s=45]

⇒r=60

Hence the value of r when s = 45 is 60.