Question

Question 65

l varies directly as m and l =5, when $m=\frac{2}{3}$. Find l when m $=\frac{16}{3}$

Answer 1

If l varies directly as m.
$\therefore \frac{l}{m}=\frac{5}{\frac{2}{3}}...\left(i\right)=\frac{5}{1}\times \frac{3}{2}=\frac{15}{2}\Rightarrow k=\frac{15}{2}$

When $m=\frac{16}{3}$, then from Eq (i)
$\frac{l}{\frac{16}{3}}=\frac{15}{2}$ [Putting the value of k]
$\Rightarrow l=\frac{15}{2}\times \frac{16}{3}=40$