Question
The average ages of A, B and C is 20% more than the
average ages of A and B. 10years hence from now, the ratio of the ages of A and C will be 3:5, respectively and age of B will be the mean of their ages at the time. Find the sum of present ages of B and C.Solution
Let the age of A and C 10 years from now we 3X years and 5X year respectively. So age of B 10 years from now = (3X+5X)/2 = 4x years. As per question (3x-10+4x-10+5x-10)/3 = 1.2*(3x-10+4x-10)/2 24x-60 = 3.6*(7x-20) 24x-60 = 25.2x-72 1.2x=12 X=10 Sum of present age of B and C = (4*10-10) +(5*10-10) = 70 years.
900 Â Â Â 90Â Â Â 18Â Â Â ? Â Â Â Â 2.16Â Â Â Â 1.08
78, 80, 84, ?, 108, 140
5 6 14 45 ? 925
...1, 26, 75, 156, 277, ?
138, 140, 152, 174, ?, 248
11, ? 220,  660, 1320,  1320Â
114, 134, 174, 254, 414, ?Â
14 6 4 4 ? 48
...What should come in place of (?) question mark in the following number series.
5, 11, 23, 47, 95, ?
7, 8, 18, 57, 232, ?