77.
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Divya is twice as old as Shruti. What is the difference in their ages?
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I.
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Five years hence, the ratio of their ages would be 9 : 5.
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II.
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Ten years back, the ratio of their ages was 3 : 1.
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I alone sufficient while II alone not sufficient to answer
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II alone sufficient while I alone not sufficient to answer
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Either I or II alone sufficient to answer
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Both I and II are not sufficient to answer
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Both I and II are necessary to answer
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Answer: Option C
Explanation:
Let Divya's present age be D years and Shruti's present age b S years
Then, D = 2 x S D - 2S = 0 ....(i)
I.
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D + 5
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=
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9
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....(ii)
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S + 5
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5
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II.
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D - 10
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=
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3
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....(iii)
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S - 10
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1
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From (ii), we get : 5D + 25 = 9S + 45 5D - 9S = 20 ....(iv)
From (iii), we get : D - 10 = 3S - 30 D - 3S = -20 ....(v)
Thus, from (i) and (ii), we get the answer.
Also, from (i) and (iii), we get the answer.
I alone as well as II alone give the answer. Hence, the correct answer is (C).
