Find the biggest negative value of a , for which the maximum of

$f(x)=sin(24x+\frac{\pi a}{100})$ is at ${x}_{0}=\pi $

The answer is $a=-150$ , but I don't understand the solving way. I would appreciate if you'd help me please

$f(x)=sin(24x+\frac{\pi a}{100})$ is at ${x}_{0}=\pi $

The answer is $a=-150$ , but I don't understand the solving way. I would appreciate if you'd help me please