# Aptitude - Averages Online Quiz

Following quiz provides Multiple Choice Questions (MCQs) related to **Averages**. You will have to read all the given answers and click over the correct answer. If you are not sure about the answer then you can check the answer using **Show Answer** button. You can use **Next Quiz** button to check new set of questions in the quiz.

Q 1 - Find the average of the numbers which are as follows : 15, 5, 0, 12, 8

### Answer : C

### Explanation

Average required = (15+5+0+12+8)/5 = 40/5 = 8

Q 2 - 28 is the average of 3 numbers. Find out the value of third number if the given condition is such that the second number have the double value in the comparison of first number and third number have 4 times value of first number?

### Answer : A

### Explanation

If x is the value of third number. Then the value of second number is x/2 , if x/2 is the value of second number then the value of first number will be 1/2 . x/2 = x/4. Total sum of three number = (3*28) =84 ∴ x+x/2+x/4 = 84 ⇒ 7x/4 = 84 ⇒ x= (84*4)/7 = 48 So, its proves that the value of the third number is 48.

Q 3 - An organization has 400 workers including officers. Rs. 10000 is the average salary of officers and Rs. 2000 is the labor average monthly salary. If Rs. 3000 is the total average salary of 400 workers then what should be the number of officers in the organization?

### Answer : A

### Explanation

If x is the number of officer in an organization. In that situation the number of workers will be (400-x). 10000x+ 2000 (400-x)= 400* 3000 ⇒ 10000x+ 800000-2000x =1200000 = 8000x = 1200000-80000 ⇒ x = 50 Total number of officer working in organization is 50.

Q 4 - A hostel have 35 students if 42 student became in the hostel then expenditure on per student increase and became Rs. 42 per head while Rs. 1 reduce in the average expenditure. Find out the expenditure per day at the present time?

### Answer : D

### Explanation

If x is the original expenditure , then x/35- (x+42)/42 = 1 =. 6x -5(x+42)= 210 ⇒ x= 420 ∴ original expenditure = Rs. 420

Q 5 - find out the total value of 6 numbers if 45 is the arithmetic mean of 6 numbers.

### Answer : D

### Explanation

a,b,c,d,e,f is the given 6 numbers .Then , (a+b+c+d+e+f)/6 = 45 = (a+b+c+d+e+f) = 45*6 = 270. Sum of the given numbers = 270.

Q 6 - Drinks were done by 6 persons. Out of them 5 person paid 32 Rs. each, Rs. 80 more paid by the 6th person in the comparison of average expenditure of all. Find out the total amount paid by 6 persons?

### Answer : A

### Explanation

if x is the average expenditure of 6 person. (32*5)+(x+80)= 6x = 5x = (160+80) = 5x= 240 ⇒ x = 48 Total expenditure = 48*6 =288 Rs.

Q 7 - The average price of 10 books is Rs. 12 while the average price of 8 of these books is Rs. 11.75. Of the remaining two books, if the price of one book is 60% and more than the price of the other, what is the price of each of these two books?

**Answer - C**

**Explanation**

Total price of the two books = Rs. [(12 x 10) - (11.75 x 8)] = Rs. (120 - 94) = Rs. 26. Let the price of one book be Rs. z. Then, the price of other book = Rs. (z + 60% of z) = Rs. ( z +^{3z}⁄_{5}) = Rs.^{8z}⁄_{5}So, z +^{8z}⁄_{5}= 26 = 13z = 130 = z = 10. Therefore The price of the two books are Rs. 10 and Rs. 16.

Q 8 - The mean of 50 observation was 36. It was found later that an observation 48 was wrongly taken as 23. The corrected new mean is?

**Answer - A**

**Explanation**

Correct sum = (36 x 50 + 48 - 23) = 1825. Therefore Correct Mean =^{1825}⁄_{50}= 36.5.

Q 9 - The average monthly salary of 20 employees in an organisation is Rs. 1500. If manager's salary is added, then the average salary increases by Rs. 100. What is the manager's monthly salary?

**Answer - B**

**Explanation**

Manager's monthly = (16000 x 21 - 1500 x 20) = Rs. 3600.

Q 10 - The average age of students of a class is 15.8 years. The average age of boys in the class is 16.4 years and that of the girls is 15.4 years. The ratio of the number of boys to the number of girls in the class is?

**Answer - B**

**Explanation**

Let the ratio be k : 1. then, k x 16.4 + 1 x 15.4 = (k + 1) x 15.8 (16.4 - 15.8) k = (15.8 - 15.4) k =^{0.4}⁄_{0.6}=^{2}⁄_{3}