Question

if p varies directly as q and if p = 21 when q = 7 , then find q when p = 15.​

Answer 1

Answer:5

Step-by-step explanation:

If p=21

Q=7

Since 7×3=21

Therefore if p=15

Q=5

Since 5×3=15

Answer 2

If $p=15$ then $q=5$

Step-by-step explanation:

According to the question it states that p is directly varying with q meaning that both are directly proportional.

So, $p$ ∞ $q$ and $p=kq$ as to remove proportionality we place a constant term here it is $k$

We have to find the value of the constant $k$.

⇒For this we can say that, $k=\frac{p}{q}$

And $k=\frac{21}{7} =3$

⇒Now we can say that $p$ and $q$ are varying with a factor of $3$.

Let use this constant value and find the value of $q$ when $p=15$

$p=kq$ then $q=\frac{p}{k} = \frac{15}{3}=5$

So the value of $q=5$ when $p=15$