Question

divide 140 among A, B, and C so that B may get twice and C may get thrice as much as A

Answer 1

a+b+c = 140

a = a
c = 3a
b = 2*3a = 6a

so,
a+6a+3a = 140
10a = 140
a = 14

so,
a = 14
b = 84
c = 42

Answer 2

A+B+C=140 ..... (i)
given
B=2A
C= 3A
put this in (i)
A+2A+3A=140
6A=140
A= 23.33 nearly 23.33
Now = B=2×23.33 =47
C= 3×23.33=70