1. Let Chandrika's mothers age now = x,
10 yrs ago her age= x-10
10 yr hence her age= x+10
According to the question, 10 yr ago Chandrika's age = (x-10)/4 yr
10 yr hence her age = (x+10)/2
Then we have (x-10)/4 + 20 = (x+10)/2
Solving x -10 + 80 = 2x +20
x = 50
Present age of Chandrika's mother is 50 yrs.
2. Let the consecutive no.s be x-1, x and x+1
ATQ (x-1) + 2(x+1) = 4x -7
⇒ x-1 + 2x +2 = 4x -7
⇒ x = 8
Then we have the numbers 8-1, 8, 8+1 i.e 7,8,9