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Question
Three years hence, the ages of Radha and Meena will be in the ratio 5 : 2. If the sum of their present ages is 62 years, their ages, 2 years ago, were:
Options
43 years and 19 years
41 years and 17 years
40 years and 16 years
none of these
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Solution
none of these
Explanation:
Let the present ages of Radha and Meena be a and b.
It is given, three years hence, the ages of Radha and Meena will be in the ratio 5 : 2.
⇒ `(a + 3)/(b + 3)` = 52
⇒ 2(a + 3) = 5(b + 3)
⇒ 2a + 6 = 5b + 15
⇒ 2a = 5b + 15 − 6
⇒ 2a = 5b + 9
⇒ a = `(5b + 9)/2` ....(1)
The sum of their present ages = 62 years.
The sum of their present ages = 62 years.
⇒ a + b = 62
Substituting the value of a from equation (1), we get
⇒ `(5b+9)/2 + b = 62`
⇒ 5b + 9 + 2b = 124
⇒ 7b + 9 = 124
⇒ 7b = 124 − 9
⇒ 7b = 115
⇒ b = `115/7`
Substituting the value of b in equation (1),
⇒ a = `(5 xx 115/7 + 9)/2`
⇒ a = `(575 + 63)/14`
⇒ a = `638/14`
⇒ a = `319/7`
Radha's age 2 years ago = a − 2
= `319/7 - 2`
= `(319 - 14)/7`
= `305/7`
= 43.57
Meena's age 2 years ago = b − 2
= `115/7 - 2`
= `(115 - 14)/7`
= `101/7`
= 14.42
