Five years ago the average of the ages of A and B was 40 years and now the average of the ages of B and C is 50 years. What will be the age of the B ten years hence?	Choose one.
A) 39
B) 23
C) 28
D) 96
E) 100
Let the present ages of A, B and C be a, b and c respectively.   Given, [(a - 5) + (b - 5)] / 2 = 40 =&gt; a + b = 90 --- (1)   (b + c)/2 = 50 =&gt; b + c = 100 --- (2)   Answer: 100
<result>E</result>
Five years ago the average of the ages of A and B was 40 years and now the average of the ages of B and C is 50 years. What will be the age of the B ten years hence?