Mathematics Mcqs

A. 125
B. 134
C. 170
D. 98
Sum of the 35 numbers = 35 * 25 = 875
If each number is multiplied by 5, the sum also gets multiplied by 5 and the average also gets multiplied by 5.
Thus, the new average = 25 * 5 = 125

A. 3000
B. 2500
C. 4500
D. 5000
Sum of the salaries of the person for the months of January, February, March and April = 4 * 8000 = 32000 —-(1)
Sum of the salaries of the person for the months of February, March, April and May = 4 * 8500 = 34000 —-(2)
(2)-(1) i.e. May – Jan = 2000
Salary of May is Rs.6500
Salary of January = Rs.4500

A. 50
B. 47.5
C. 59
D. 52.5
Sum of the marks for the class of 30 students = 30 * 40 = 1200
Sum of the marks for the class of 50 students = 50 * 60 = 3000
Sum of the marks for the class of 80 students =
1200 + 3000 = 4200
Average marks of all the students = 4200/80 = 52.5

A. 17
B. 29
C. 18
D. 19
Let the average after the 16th inning be P.
So, the average after the 15th inning will be (P-3) Hence, 15(P-30) + 64 = 16P => P = 19

A. 46
B. 32
C. 68
D. 51
Explanation:
Sum of all the 13 numbers = 13 * 60 = 780
Sum of the first 7 of them = 7 * 57 = 399
Sum of the last 7 of them = 7 * 61 = 427
So, the 8th number = 427 + 399 – 780 = 46

A. 10
B. 11.5
C. 12
D. 10.5
Explanation:
Average of the first ‘n’ natural numbers = (n + 1)/2
We get (20 + 1)/2 = 10.5

A. 46
B. 56
C. 34
D. 57
Explanation:
1 to 11 = 11 * 50 = 550
1 to 6 = 6 * 49 = 294
6 to 11 = 6 * 52 = 312
6th = 294 + 312 – 550 = 56

A. 1
B. 10
C. 12.5
D. 50
Explanation:
5 * 46 – 4 * 45 = 50

A. 1 year
B. 1.5 years
C. 2 years
D. 2.5 years
6 * 22 = 132
7 * 19 = 133
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1

A. 1540
B. 960
C. 840
D. 1020