Answer:
We get Q=63 when p=81
Option A is correct.
Step-by-step explanation:
We are given that [tex]Q \propto \sqrt{p}[/tex]
We can write it as [tex]Q=k\sqrt{p}[/tex]
Where k is constant of proportionality.
We are given Q = 21 when p = 9
Using this Q = 21 when p = 9 we can find value of k
[tex]Q=k\sqrt{p}\\k=\frac{Q}{\sqrt{p} }\\k=\frac{21}{\sqrt{9} } \\k=\frac{21}{3}\\k=7[/tex]
So, we get constant of proportionality k = 7
Now, Finding the value of Q when p = 81
We are given p=81, k=7, we need to find Q
Using the equation [tex]Q=k\sqrt{p}[/tex] we can find value of Q.
[tex]Q=k\sqrt{p}\\Q=7\sqrt{81}\\Q=7\times 9\\Q=63[/tex]
So, we get Q=63 when p=81
Option A is correct.
