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The Age of the Father is Seven Times the Age of the Son. Ten Years Later, the Age of the Father Will Be Thrice the Age of the Son. Find Their Present Ages.

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प्रश्न

The age of the father is seven times the age of the son. Ten years later, the age of the father will be thrice the age of the son. Find their present ages.

योग
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उत्तर

Let the present age of father = x years and that of son = y years
After 10 years,
father's age = (x + 10) years
son's age = (y + 10) years
According to given information, we have
x = 7y   ....(i)
And,
(x + 10) = 3(y + 10)
⇒ x + 10 = 3y + 30
⇒ x - 3y = 20
⇒ 7y - 3y = 20        ...[From (i)]
⇒ 4y = 20
⇒ y = 5
⇒ x = 7 x 5
= 35
Thus, the present age of son is 5 years and that of father is 35 years.

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Methods of Solving Simultaneous Linear Equations by Elimination Method
  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 5: Simultaneous Linear Equations in Two Variables - Exercise 8.3

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फ्रैंक Mathematics Part 1 [English] Class 9 ICSE
अध्याय 5 Simultaneous Linear Equations in Two Variables
Exercise 8.3 | Q 12

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