$ I_{min} \propto (a_1 - a_2)^2$ 

$\text {here } a_1 = 2a , a_2 = a ,\text{because width of one slit is doubled as compared to other}$

$\Rightarrow I_{min} \propto (2a - a)^2 = a^2$ 

$ I_{max} \propto (a_1 + a_2)^2$ 

$\text {here } a_1 = 2a , a_2 = a ,\text{because width of one slit is doubled as compared to other}$

$\Rightarrow I_{min} \propto (2a + a)^2 = 9 a^2$ 

$\text{Intensity of both maxima and minima increases}$