book Maths Puzzle Numerical Ability

please help me with this problem i think it's correct but not sure 1/2(550+x)/20=25 2/1x25/1=2/1x1/2(550+x)/20 50=550+x/20 20/1x50/1=550+x/20x20/1 1000=55

Read Solution (Total 0)

book Other Question
determine the probability of getting a zero heads when tossing a coin four times. Expand:

abc((a + b^2 + c^3)c) =

Please show your working out


Thanks in advance for your help