If Mamun were twice as old as he is now, he would be 40 years older than Jamal. If Jamal is 10 years younger than Mamun, how old is Mamun?
A
20
B
30
C
40
D
50
Correct Answer: 30
Ler, Jamal = x Mamun = x + 10 2 ( x + 10) = x + 40 x = 20 Now, Mamun is ( 20 + 10) = 30