Averages Quiz Set 010


Your Score
Correct Answers:
Wrong Answers:
Unattempted:

Question 1

A box contains 5 marbles each having a weight of 108 grams. The box also contains 25 marbles each having a weight of 72 grams. What is the average weight of all the marbles in the box?

 A

78 grams.

 B

79 grams.

 C

77 grams.

 D

76 grams.

Soln.
Ans: a

The weighted average = ${5 × 108 + 25 × 72}/30$, which equals ${540 + 1800}/30$ = 78.


Question 2

Each of the 8 girls of a class has a score 28 marks. If a new girl with a score 56 marks more than the average of all 9 girls is added, what is the sum total of the values of all 9 girls?

 A

315 marks.

 B

316 marks.

 C

314 marks.

 D

313 marks.

Soln.
Ans: a

Let the average of all 9 girls be x, then the required total is T = 9x. By averages, $x = {8 × 28 + (x + 56)}/9$ which is same as $x × 9 = {8 × 28 + (x + 56)}$, which is same as $T = {8 × 28 + (T/9 + 56)}$, solving for T we get 315 marks.


Question 3

The average weight of the 17 bogies of a train increases by 13 Kg when a new bogie replaces a bogie of weight 9 Kg. What is the weight of the new bogie.

 A

230.

 B

231.

 C

229.

 D

232.

Soln.
Ans: a

The total increase of weight = 17 × 13 = 221. So the weight of the new bogie = 9 + 221 = 230 Kg.


Question 4

387 men and 258 women are employed in a farm. The average wage per person is Rs. 128. What is the wage of a man if women are paid Rs. 5 less?

 A

Rs. 130.

 B

Rs. 131.

 C

Rs. 129.

 D

Rs. 132.

Soln.
Ans: a

Let the wage of a man and a woman be x and x - 5. We are given the average ${x × 387 + (x - 5) × 258}/{387 + 258}$ = 128. This equation can be solved for x to get Rs. 130 as the answer.


Question 5

The average weight of 16 students of a class is 31 Kg, whereas the average weight of remaining 16 students is 28 Kg. What is the average weight of all 32 students?

 A

$29{1/2}$.

 B

$30{14/31}$.

 C

$28{20/33}$.

 D

$31{7/15}$.

Soln.
Ans: a

Total weight of 16 students is 16 × 31 = 496. Similarly, the total weight of remaining 16 students is 16 × 28 = 448. The total weight of all 32 students is 496 + 448 = 944. So the average = 944/32 = $29{1/2}$.


buy aptitude video tutorials


Creative Commons License
This Blog Post/Article "Averages Quiz Set 010" by Parveen (Hoven) is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.
Updated on 2020-02-07. Published on: 2016-04-22

Posted by Parveen(Hoven),
Aptitude Trainer


Comments and Discussion