there is no option here for making diagram is it?
Is the shaded area enclosed by the four circles?
Here is a way to do it.
Link the four centers of the circles to get a square. Take a whole circle's area away from the square's area.
The shaded area = 24^2 - pi(12^2) cm^2
Can you finish the calculation?
Attn: Actually, you take away 4 quarter circles' area away, which is equal to a whole circle's area.