Question

if sum of age of the husband and wife is 76 years. if ratio of their age before 20years is 5:4 then find their present age.

Answer 1

Hi friend
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Your answer
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SOLVING (BY METHOD OF SUBSTITUTION)
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Let the present age of the husband be x and that of the wife be y.

Then,
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According to the question,
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Equations : -
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x + y = 76 .......(i)

(x - 20)/(y - 20) = 5/4 .....(ii)

From equation (i), we get,
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x = 76 - y ......(iii)

Now,
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Solving equation (ii), we get,
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(x - 20)/(y - 20) = 5/4

=> 4(x - 20) = 5(y - 20)

=> 4x - 80 = 5y - 100

=> 4(76 - y) = 5y - 100 + 80 [From (iii)]

=> 304 - 4y = 5y - 20

=> 5y + 4y = 304 + 20

=> 9y = 324

=> y = 324/9

=> y = 36

Then,
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x = 76 - y = 76 - 36 = 40

Therefore,
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Husband's present age = 40 years

Wife's present age = 30 years

HOPE IT HELPS