# Mathematical Aptitude - Averages

>>>>>>>>Averages

• Option : B
• Explanation : Total of A and B = (5,050 × 2) = 10,100 (i)
Similarly, total income of B and C = (6250 × 2) = 12,500 (ii)
And total of A and C = (5200 × 2) = 10,400 (iii)
Adding (i), (ii), and (iii), we get, 2(A + B + C) = 33,000
Or A + B + C = 16,500
But B + C = 12,500 from Equation (ii)
Hence, A = 16,500 − 12,500 = 4000

• Option : C
• Explanation : Total increase in weight = (8 × 2.5) kg = 20 kg
Weight of new person = (60 + 20) kg = 80 kg

• Option : C
• Explanation : Total weight of 8 articles = 200 kg
Total weight of 3 articles = 3 × 20 = 60 kg
Total weight of rest of 5 articles = 200 − 60 = 140 kg
Average weight of 5 articles = 140/5 = 28 kg

• Option : C
• Explanation : As the distance is not mentioned, L.C.M. of 35 and 42, that is, 210 can be assumed to be the total distance.
Time taken from A to B = 210/35 = 6 hours
Time taken from B to A= 210/42 = 5 hours
Total Time taken = 11 hours
Average speed = (210 + 210)/(6 + 5) = 420/11 = 38.17 kmph
Alternatively, by applying direct formula
= 2xy/(x+y)
= (2*35*42)/35+42 = 38.17kmph

• Option : C
• Explanation : Petrol consumed during 1st year = 4000/8 = 500
Petrol consumed during 2nd year = 4000/10 = 400
Total expenditure = 4000 × 2 = 8000
Total petrol consumed = 500 + 400 = 900
Average cost per litre = 8000/900 = Rs 8.88
Note: The answer won’t be Rs 9 as many have thought because calculation of average also depends upon quantity consumed. This question can be solved with harmonic mean also.

## Description

• Averages Questions can be used to give quizzes by any candidate who is preparing for UGC NET Paper 1
• This Averages Questions section will help you test your analytical skills in a tricky method, thereby giving you an edge over other students
• All candidates who have to appear for the Kendriya Vidyalaya Entrance exam can also refer to this mcq section.