RRB NTPC SAMPLE PAPER - ARITHMETIC - 84

1. Of the three numbers whose average is 60, the first is one fourth of the sum of the others. The first number is

(a) 30
(b) 36
(c) 42
(d) 45

2. The average of 11 numbers is 10.8. If the average of the first six be 10.4 and that of the last six is 11.5, then the middle (6th) number is

(a) 10.3
(b) 12.6
(c) 13.5
(d) 15.5

3. The average age of 12 players of a team is 25 years. If the captain’s age is included, the average age increases by 1 year. The age of the captain is :

(a) 25 yrs.
(b) 38 yrs.
(c) 36 yrs.
(d) 26 yrs.

4. The average income of 40 persons is Rs. 4200 and that of another 35 persons is Rs. 4000. The average income of the whole group is:

(a) Rs. 4100
(b) Rs. 4106 3
(c) Rs. 410623
(d) Rs. 4108 3

5. The length of the diagonal of a square is ‘a’ cm. Which of the following represents the area of the square (in sq. cm.) ?

(a) 2a
(b) a /√2
(c) a²/2
(d) a²/4

Railway Recruitment Board (RRB) NTPC Exams Study Kit

Answer:

1. (b) 2. (b) 3. (b) 4. (c) 5. (c)