Given that A, B ,C, D and E went to a restaurant and paid the bill together.
A paid = 1/2
B paid = 1/5
We need to find out the fraction of the bill paid by C,D and E.
Let us consider the fraction paid by C,D and E be = X
As the bill is paid by all together so let consider the whole bill as 1.The bill is taken as whole so the bill is 1
So combining all the above data, the equation becomes
A + B + C + D + E = 1
1/2 + 1/5 + x + x + x = 1
(5 + 2)/10 + 3x = 1
7/10 + 3x = 1
7+30X / 10 = 1
7+30X = 10
x = 3/30
x = 1/10
Therefore the fraction of bill paid by C,D and E is 1 /10