Mathematics
Number System
Find the next number in the series: 11, 28, 45, 62, 79, ?
A. 113
B. 96
C. 130
D. 79
Correct Answer: B
The common difference is 17. So the next term is 79 + 17 = 96.
Mathematics
Number System
Find the next number: 6, 22, 47, 83, 132, ?
A. 204
B. 196
C. 188
D. 181
Correct Answer: B
The increments are consecutive squares: 16, 25, 36, 49; next add 8² = 64. So the answer is 196.
Mathematics
Number System
Find the next term: 25, 45, 73, 109, 153, ?
A. 205
B. 209
C. 149
D. 261
Correct Answer: A
The terms follow 4n² + 9 for consecutive n. For n = 7, the term is 4×7² + 9 = 205.
Mathematics
Number System
Find the next number in the series: 77, 82, 87, 92, 97, ?
A. 112
B. 107
C. 102
D. 97
Correct Answer: C
The common difference is 5. So the next term is 97 + 5 = 102.
Mathematics
Number System
What digit x makes the number 741x divisible by 9?
A. 1
B. 9
C. 6
D. 7
Correct Answer: C
A number is divisible by 9 when its digit sum is divisible by 9. Thus 7+4+1+x must be a multiple of 9, giving x = 6.
Mathematics
Number System
A two-digit number is 52. What is the absolute difference between the number and the number formed by reversing its digits?
A. 27
B. 3
C. 18
D. 36
Correct Answer: A
Reversed number = 25. Absolute difference = |52 - 25| = 27.
Mathematics
Number System
How many positive divisors does 21 have?
A. 3
B. 4
C. 6
D. 5
Correct Answer: B
21 = 7^1 × 3^1. Number of divisors = (1+1)(1+1) = 4.
Mathematics
Number System
What is the remainder when 536 is divided by 7?
A. 6
B. 4
C. 0
D. 5
Correct Answer: B
536 = 7 × 76 + 4; therefore the remainder is 4.
Mathematics
Number System
Find the next term: 12, 20, 32, 52, 84, 136, ?
A. 252
B. 220
C. 272
D. 168
Correct Answer: B
Each term is the sum of the previous two. Therefore 84 + 136 = 220.
Mathematics
Number System
Find the next number in the alternating series: 4, 78, 6, 76, 8, 74, ?
A. 8
B. 10
C. 72
D. 12
Correct Answer: B
Odd-position terms are 4, 6, 8, ... with difference 2. Hence the next odd-position term is 10.
Mathematics
Number System
What least number must be subtracted from 886 so that the result is exactly divisible by 9?
A. 3
B. 13
C. 5
D. 4
Correct Answer: D
The remainder is 4; subtracting the remainder makes the number divisible by 9.
Mathematics
Number System
Find the next term in the series: 8, 13, 20, 29, 40, ?
A. 64
B. 55
C. 51
D. 53
Correct Answer: D
The first differences are [5, 7, 9, 11]; their second difference is constant at 2. Continuing the pattern gives 53.
Mathematics
Number System
How is the integer 55 classified?
A. Neither prime nor composite
B. Irrational
C. Prime
D. Composite
Correct Answer: D
55 = 11 × 5, so it has factors other than 1 and itself and is composite.
Mathematics
Number System
Classify √61.
A. Rational
B. Irrational
C. Whole number
D. Prime number
Correct Answer: B
61 is not a perfect square, so √61 is irrational.
Mathematics
Number System
A two-digit number is 29. What is the absolute difference between the number and the number formed by reversing its digits?
A. 7
B. 72
C. 54
D. 63
Correct Answer: D
Reversed number = 92. Absolute difference = |29 - 92| = 63.
Mathematics
Number System
A two-digit number is 46. What is the absolute difference between the number and the number formed by reversing its digits?
A. 27
B. 18
C. 9
D. 2
Correct Answer: B
Reversed number = 64. Absolute difference = |46 - 64| = 18.
Mathematics
Number System
How many trailing zeros are there in 78! ?
A. 7
B. 17
C. 18
D. 19
Correct Answer: C
Trailing zeros = ⌊78/5⌋ + ⌊78/25⌋ + ... = 15 + 3 = 18.
Mathematics
Number System
Classify 19/17.
A. Prime number
B. Irrational
C. Rational
D. Whole number
Correct Answer: C
19/17 is a ratio of two integers with a non-zero denominator, so it is rational.
Mathematics
Number System
Find the next number in the series: 4, 12, 36, 108, 324, ?
A. 327
B. 324
C. 972
D. 975
Correct Answer: C
Each term is multiplied by 3. Therefore 324 × 3 = 972.
Mathematics
Number System
Find the missing number: 85, 91, 97, ?, 109, 115
A. 109
B. 115
C. 97
D. 103
Correct Answer: D
This is an arithmetic series with common difference 6; the missing term is 103.