Sorry, before i proceed to help, may i know if you have learned to use the square root function on your calculator yet in your syllabus?

No need of calculator :)

area of p+q = 1/9 + 1/6 of square
which is = 5/18th of the area of square.

so area of square= 10*18/5= 36 cm2.

side of the square= 6 cm.(ans a)

now area of P = 1/9 * 36 = 4 cm2.
so 1/2 * 6 * base of P = 4
so base of P = 4/3 cm

so height of S = 6-4/3 = 14/3cm
area of S = 1/2 * 14/3* 6= 14 cm2

Thus fraction of S = 14/36=7/18.(ans b)