a
$\frac{I_{\max }}{I_{\min }}=\frac{(a+b)^{2}}{(a-b)^{2}}$
$=\frac{49}{9}$
where $a, b$ are the amplitudes $\frac{a+b}{a-b}=\frac{7}{3}$
$3 a+3 b=7 a-7 b$
or, $4 a=10 b$
or, $\frac{a}{b}=\frac{10}{4}=\frac{5}{2}$
also we know, $\frac{I_{1}}{I_{2}}=\frac{a^{2}}{b^{2}}=\left(\frac{a}{b}\right)^{2}=\frac{25}{4}$
So the intensity ratio of component waves $6.25$