# Average [NRA CGL (National Recruitment Agency-Combined Graduate Level) Mathematics]: Questions 15 - 19 of 25

Access detailed explanations (illustrated with images and videos) to 425 questions. Access all new questions- tracking exam pattern and syllabus. View the complete topic-wise distribution of questions. Unlimited Access & Unlimited Time!

View Sample Explanation or View Features.

Rs. 300.00 -OR-

How to register? Already Subscribed?

## Question 15

Average
Edit

### Question

MCQ▾

In a school with 900 students, the average age of boys is 12 years and that of the girls is 11 years and 6 months. If the average age of the school is 11 years and 9 months, then the number of the girls in the school is

### Choices

Choice (4)Response

a.

390

b.

450

c.

760

d.

460

## Question 16

Average
Edit

### Question

MCQ▾

The average marks of 30 students in a test is 60. Later it is found that three marks 55,65& 50 were wrongly entered as 53,68 & 59. The average marks after mistakes were rectified is

### Choices

Choice (4)Response

a.

95.67

b.

59.67

c.

d.

## Question 17

Average
Edit

### Question

MCQ▾

The average age of 40 students of a class is 10 years. When 20 new students are admitted, the average age is increased by 0.5 years. The average age of new students is (Paper- I)

### Choices

Choice (4)Response

a.

11.3 years

b.

11.2 years

c.

11.4 years

d.

11.5 years

## Question 18

Average
Edit

### Question

MCQ▾

The average weight of 8 persons decreases by 5 kg when one of them weighing 120 kg is replaced by a new person. The weight (in kg) of the new person is (Paper -I)

### Choices

Choice (4)Response

a.

68

b.

80

c.

74

d.

77

## Question 19

Average
Edit

### Question

MCQ▾

The average weekly salary of A, B and C is Rs. 5000 and that of B, C and D is Rs. 6000. If the weekly salary of A is Rs. 3000 then the weekly salary of D is (Paper - I)

### Choices

Choice (4)Response

a.

Rs. 6300

b.

Rs. 6000

c.

Rs. 6054

d.

Rs. 6050