Question 1152652: in four years time khairul's mother will be three times as old as khairul.six years ago,his mother was seven times as old as him.find:khairul's present age,the age of his mother when he was born
Found 2 solutions by Boreal, MathTherapy:
Answer by Boreal(15235)   (Show Source):
You can put this solution on YOUR website! K is x
In four years, he will be x+4 and his mother will therefore be 3(x+4)
Six years ago, he was x-6 and his mother was 7(x-6).
In 10 years his mother went from 7(x-6) to 3(x+4)
so their difference is 10
7x-42+10=3(x+4), since 7x-42 is 10 years less than 3x+12
7x-32=3x+12
4x=44
x=11 age of K now
in 4 years he will be 15 and his mother 45.
Six years ago he was 5 and his mother 35
Therefore, his mother was 30 when he was born.
She is now 41.
Answer by MathTherapy(10552)  (Show Source):
You can put this solution on YOUR website!
in four years time khairul's mother will be three times as old as khairul.six years ago,his mother was seven times as old as him.find:khairul's present age,the age of his mother when he was born
Let mother's and Khairul's ages be M and K, respectively
Then we get: M + 4 = 3(K + 4)____M = 3K + 8 ----- eq (i)
M - 6 = 7(K - 6)____M = 7K - 36 ----- eq (ii)
3K + 8 = 7K - 36 ------ Equating eqs (i) & (ii)
3K - 7K = - 36 - 8
- 4K = - 44
K, or 
M = 3(11) + 8 ------ Substituting 11 for K in eq (i)
M, or mother is 33 + 8 = 41 years-old
The difference in their ages is: 41 - 11 =  , and so thatw's the age of the mother upon Khairul's birth.
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