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प्रश्न
Choose the most appropriate option.
The age of father 10 years ago was three times the age of his son. After 10 years, father’s age is twice that of his son. The ratio of their present ages is:
विकल्प
7:3
7:4
11:7
9:5
उत्तर
7:3
Explanation:
Let son's age 10 years ago = x
Father's age 10 years ago = 3x
According to question,
2(x+20) = (3x+20)
⇒ 2x+40 = 3x+20
∴ x = 20
∴ 10 years ago, father's age = 3x = 3 × 20 = 60 years and
son's age = x = 20 years
∴ Ratio of present age = 70 : 30 = 7 : 3.
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