Question

present age of sangini mother is four times sangini age .five years henes her ae willbe 21years more than sangini age.

Answer 1

Let the present age of Sangini = x years
Therefore Sangini's mother present age = 4x years
After five years 
Sangini's age = x+5 years
Sangini's mother age(4x+5) = 21+(x+5) years
According to the sum
4x+5 = x+26
3x = 21
x = 7 years
Sangini present age = 7 years
Sangini's mother present age = 4x = 4*7 = 28 years

Answer 2

Hi Kumar ,
Let  Sangini's present age = s
Let Sangini's mother's age = m

Given

Present age of sangini's mother is four times sangini's age
m = 4s

five years hence her age will be 21years more than sangini age.
Note : '5 years hence' means after 5 years
 so here
(m+5) = 21+ (s+5)

solving above two equations
4s + 5 = 21 + s + 5
4s-s = 21 + 5 -5
3s = 21
s = 21/3
s = 7 years

m = 4s = 4*7 = 28 years

so Sangini's age is 7 years and her mother's age is 28 years.


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