PROBLEMS BASED ON AGES – 02

Question: A man’s age is 150% of what it was 10 years ago, but 75% of what it will be after 10 years. What is his present age? [एक व्यक्ति की उम्र उसके 10 वर्ष पहले की उम्र का 150% है; जबकि 10 वर्ष बाद की उसकी उम्र का यह 75% होता है. तो, उसकी वर्तमान उम्र क्या है?] [Ans. (b) 30 years]                                                                                                                         

(a) 25 yrs    (b) 30 yrs    (c) 35 yrs   (d) 40 yrs   (e) none of these

Detailed Explanation:

First Method: If the age of the man, 10 years ago is taken as 100%, then his present age becomes 150%. Obviously,  difference between the ages at these two stages is (150-100)% = 50%, but the difference is 10 years.

So, if 50% is equivalent to 10 years, then 150% (present age) should be definitely 30 years. Ans.  

    Difference = 50% ≡ 10 years

Present age = 150% ≡? = 30 years Ans.

Second Method: If the age of the man, 10 years hence is taken as 100%, then his present age becomes 75%. Obviously,  difference between the ages at these two stages is (100-75)% = 25%, but the difference is 10 years.

So, if 25% is equivalent to 10 years, then 75% (present age) should be definitely 30 years. Ans.  

  Difference = 25% ≡ 10 years

Present age = 75% ≡? = 30 years Ans.