Lakshya Education MCQs

Question:

  1. The average age of A and B is 20 years. If C were to replace A, the average would be 19 and if C were to replace B, the average would be 21. The ages of A, B and C are (in years)

Options:
A.23, 17 , 16
B.23, 16, 17
C.22, 18 , 20
D.18 ,  22, 20
Answer: Option C

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More Questions on This Topic :

Question 1.

  1. A man buys 13 shirts at Rs 50 each, 15 pairs of shoes at Rs 60 each and 12 pants at Rs 65 each. The average value of each article is

Options:
  1.    55.50
  2.    58.25
  3.    59.50
  4.    62.50
Answer: Option B
Question 2.

  1. The average temperature of Delhi in the 1st four days of a month was 37°C. The average temperature for the second, third, fourth and fifth day was 39°C. If the temperature on the 1st and 5th day were in the ratio of 4 : 5, the temperature on the 1st and 5th day must have been

Options:
  1.    300C , 400 C
  2.    320C , 400 C
  3.    340C , 500 C
  4.    none of these
Answer: Option B
Question 3.

  1. The average age of 35 students in a class was 15 years 4 months. Three students of ages 18 years 1 month, 17 years 6 months and 15 years 9 months leave the class while 8 students having average age as 16 years 5 months are newly admitted. The raised average age of the class is

Options:
  1.    15 years 3 month
  2.    15 years 6 month
  3.    15 years 9 month
  4.    none of these
Answer: Option D
Question 4.

  1. The average age of a board of 8 trustees remains the same as it was 3 years ago, when one of them is replaced by a new member. The new member is younger than the trustee in whose place he has been replaced by

Options:
  1.    16 years
  2.    24 years
  3.    32 years
  4.    none of these
Answer: Option B
Question 5.

In the first 10 overs of a cricket game, the run rate was only 3.2. What should be the run rate in the remaining 40 overs to reach the target of 282 runs?

Options:
  1.    6.25
  2.    6.5
  3.    6.75
  4.    7
Answer: Option A

Required run rate = \(\left(\frac{282-(3.2\times10)}{40}\right)=\frac{250}{40}=6.25\)

Question 6.

A family consists of two grandparents, two parents and three grandchildren. The average age of the grandparents is 67 years, that of the parents is 35 years and that of the grandchildren is 6 years. What is the average age of the family?

Options:
  1.    \(28\frac{4}{7}\)
  2.    \(31\frac{5}{7}\)
  3.    \(32\frac{1}{7}\)
  4.    None of these
Answer: Option B

Required average = \(\left(\frac{67\times2+35\times2+6\times2}{2+2+3}\right)\)

=\(\left(\frac{134+70+18}{7}\right)\)

=\(\frac{222}{7}\)

=\(31\frac{5}{7}years.\)