Question

R is inversely proportional to A

R = 12 when A = 1.5
a) Work out the value of R when A = 5.
b) Work out the value of A when R = 9​

Answer 1

Part a: The value of R when
`A=5` is
`3.6`

Part b: The value of A when
`R=9` is
`2`

Step-by-step explanation:

It is given that R is inversely proportional to A.

Hence, it can be written as
`R=(k)/(A)`

Also, it is given that
`R=12` and
`A=1.5`

Substituting these values in
`R=(k)/(A)`, we have,

`12=(k)/(1.5)`

`18=k`

Thus, the value of K is
`18=k`

Part a: To determine the value of R when
`A=5`

Now, substituting
`A=5` and
`k=18` in
`R=(k)/(A)`, we get,

`R=(18)/(5)`

`R=3.6`

Thus, the value of R is
`R=3.6`

Part b: To determine the value of A when
`R=9`

Now, substituting
`R=9` and
`k=18` in
`R=(k)/(A)`, we get,

`9=(18)/(A)`

`A=(18)/(9)`

`A=2`

Thus, the value of A is
`A=2`