How much water would you add to 2 1/2 gallons of bleach to make a 10 bleach solution?

To get the amount of water you would add to 2.5 gallons of bleach to make 10% bleach we shall proceed as follows:
let the amount of water be x
100*2.5+0x=10(x+2.5)
250=10x+25
10x=225
x=22.5
thus the answer is, 22.5 gallons of pure water should be added in the bleach.

In the first triangle 80+20+p=180 (since sum of all angles of a triangle is 180)so p= 80also in second triangle 55+45+q=180 (since sum of all angles of a triangle is 180)so q=80so we can conclude that p=80 degrees q=80 degrees so p=q=80 degreeshence option b is correct