Question

If Q is inversely proportional to P and Q =0.25 when
P = 2,
(i) express Q in terms of P,
(ii) find the value of Q when P = 5,
(iii) calculate the value of P when Q = 0.2.​

Answer 1

Step-by-step explanation:

i)

Q is inversely proportional to P is written as

$Q \: \: \alpha \: \frac{k}{P}$

where k is the constant of proportionality

we must first calculate the relationship between them

So we have

when Q = 0.25

P = 2

Substitute the values into the above equation

That's

$0.25 = \frac{k}{2}$

Cross multiply

We have

k = 0.25 × 2 = 0.5

So the formula for the variation is

$Q = \frac{0.5}{P}$

ii)

when P = 5

We have

$Q = \frac{0.5}{5}$

We have the answer as

Q =0.1

iii)

When Q = 0.2

We have

$0.2 = \frac{0.5}{P}$

Cross multiply

That's

0.2P = 0.5

Divide both sides by 0.2

We have the answer as

P = 2.5

Hope this helps you