# 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 - 25 is the average of these number which are 40, 10, 25, 20, 35, x . find out the value of x?

### Answer : B

### Explanation

(40+10+25+20+35+x)/6 = 25 ⇒ 130+x = 150 = x = 20

Q 2 - 68 is the average score scored by the student in a class. 80 is the average of girls marks and 60 is the average score of boys in this class. Find out the percentage of boys in the class?

### Answer : D

### Explanation

If 100 is the total quantity of the class and x is the number of boys in the class , then the number of girls will be (100-x). 60x+ 80(100-x) = 6800 ⇒ 60x+8000-80x = 6800 = 20x = 1200 ⇒ x =60 So , its proves that that boys percentage in a class is 60%.

Q 3 - A committee have 8 person. If 35 year and 45 year aged lady replaced by two men in that case the average of age become more 2 year in the comparison of old one. Find out the average age of two men?

### Answer : D

### Explanation

Age increase = (2*8) = 16 years. Total age of two lady who replaced = (35+45)= 80 Total age of two man = (80+16) =96 Average age of those men = 96/2 = 48. Hence, is 48 the required average age.

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 - What should be the the first number if we have four numbers and given condition is that 15 is the average of first three number and last three number have 16 average if 19 is the last number given?

### Answer : A

### Explanation

let the numbers be x, x1,x2,x3,x4 ,then , x1+x2+x3 =(15*3)= 45 x2+x3+x4 =(16*3)= 48 On subtracting ,we get x4-x1=3 ∴19-x1 =3 ⇒ x1=16. First number = 16

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 of runs of a cricket player of 10 innings was 32. How many runs must he make in his next innings so as to increase his average of runs by 4?

**Answer - D**

**Explanation**

Average after 11 innings = 36. Therefore Required number of runs = (36 x 11) - (32 x 10) = 396 - 320 = 76.

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 - A cricketer has a certain average for 10 innings. In the eleventh inning, he scored 108 runs, thereby increasing his average by 6 runs. His new average is?

**Answer - B**

**Explanation**

Let average for 10 innings be z. Then, =^{10z + 108}⁄_{11}= 11z + 66 = 10z + 108 = z = 42. New average = (z + 6) = 48 runs.

Q 10 - 10 years ago. the average age of a family of 4 members was 24 years. Two children having been born, (with age difference) the present average age of the family is the same today. The present age of the youngest child is?

**Answer - B**

**Explanation**

Total age of 4 members, 10 years ago = (24 x 4) years = 96 years Total age of 4 members now = 96 + 10 x 4 yrs = 136 years Total age of 6 members now = (24 x 6) years = 144 years Sum of the ages of 2 children = (144 - 136) years = 8 years Let the age of the younger child be z years. Then, age of the elder child = (z + 2) years so, z + z + 2 = 8 2z = 6 z = 3 Therefore Age of younger child = 3 years.