Do (10 x 10) then (10 x 20), and then add your two answers together.
Its simple :)
B because distributive property goes like this:
a(b+c)
a(b)+a(c)
That's just an example though
Your answer is 7/40 or 0.175
15x15= 225
15x + 105= 225
15x= 225-105
15x= 120
X=8
X+ (x+1) + (x+2) + (x+3)…etc all the way up too +(x+14)=225
The first five numbers of the set: 8, 9, 10, 11, 12
