The ratio of the ages of the husband and the wife five years ago was 11:9 where as at the same time the ratio of the ages of the husband and his son was 5:1 .Five years hence the ratio of the ages of the husband and the wife became 13:11 . What is the sum of the present ages of all the three persons of the family ?
Answers
Answer:
Step-by-step explanation:
Given :
The ratio of a husband & his wife 5 years ago was = 11 : 9
The ratio of a husband & his son 5 years ago was = 5 : 1
The ratio of a husband & his wife 5 years after was = 13 : 11
To Find :
The sum of the present ages of all 3 persons in the family.
Solution :
Let the present age of husband be x,
Let the present age of wifw be y,
Let the present age of son be z,
Then,
The age of husband 5 years ago = x - 5
The age of wife 5 years ago = y - 5
Then,
9(x - 5) = 11(y - 5)
9x - 45 = 11y - 55
⇒ 9x - 11y = -10 ...(i)
_
The age of husband 5 years after will be x + 5
The age of wife 5 years after will be y + 5
Then,
11(x + 5) = 13(y + 5)
11x + 55 = 13y + 65
⇒ 11x - 13y = 10 ...(ii)
By solving (i) & (ii),
By subtracting 9×(ii) , from 11×(i),
We get,
11(9x - 11y) - 9(11x - 13y) = 11(-10) - 9(10)
99x - 121y - 99x + 117y = -110 - 90
-4y = -200 ⇒ y = 50
By substituting value of y in (i),
We get,
9x - 11(50) = -10
9x - 550 = -10
9x = 540 ⇒ x = 60
_
The age of son 5 years ago = z - 5,.
then,
55 = 5(z - 5)
55 = 5z - 25
30 = 5z ⇒ z = 6
∴ The sum of the present ages of the 3 persons of the family = (x + y + z) = 60 + 50 + 6 = 116
Answer:
Step-by-step explanation:
Five years ago,
H:W= 11:9
and H:S = 5:1
Hence, H:W:S =55:45:11
55k+10. =13
_________
45k+10. =11
Five years hence,
k=1
Required value =55+45+11+15=126years