Mathematics
Number System
Find the next number in the alternating series: 17, 60, 25, 58, 33, 56, ?
A. 54
B. 49
C. 33
D. 41
Correct Answer: D
Odd-position terms are 17, 25, 33, ... with difference 8. Hence the next odd-position term is 41.
Mathematics
Number System
Find the LCM of 13 and 24.
A. 343
B. 24
C. 312
D. 313
Correct Answer: C
LCM = (13 × 24) ÷ HCF(13,24) = 312.
Mathematics
Number System
What is the least positive number exactly divisible by 18, 7, and 9?
A. 126
B. 18
C. 252
D. 133
Correct Answer: A
The required number is LCM(18, 7, 9) = 126.
Mathematics
Number System
The sum of 4 consecutive integers is 250. What is the smallest integer?
A. 60
B. 65
C. 62
D. 61
Correct Answer: D
Let the integers be n, n+1, ..., n+3. Their sum is 250; solving gives n = 61.
Mathematics
Number System
What digit x makes the number 540x divisible by 9?
A. 3
B. 1
C. 0
D. 5
Correct Answer: C
A number is divisible by 9 when its digit sum is divisible by 9. Thus 5+4+0+x must be a multiple of 9, giving x = 0.
Mathematics
Number System
Find the next number in the alternating series: 9, 56, 14, 62, 19, 68, ?
A. 19
B. 74
C. 24
D. 29
Correct Answer: C
Odd-position terms are 9, 14, 19, ... with difference 5. Hence the next odd-position term is 24.
Mathematics
Number System
Find the next term in the series: 19, 30, 43, 58, 75, ?
A. 111
B. 96
C. 94
D. 92
Correct Answer: C
The first differences are [11, 13, 15, 17]; their second difference is constant at 2. Continuing the pattern gives 94.
Mathematics
Number System
Find the LCM of 25 and 14.
A. 385
B. 350
C. 25
D. 351
Correct Answer: B
LCM = (25 × 14) ÷ HCF(25,14) = 350.
Mathematics
Number System
What is the greatest multiple of 17 that is less than 3192?
A. 3180
B. 3196
C. 3179
D. 3162
Correct Answer: C
3192 ÷ 17 has integer quotient 187; 17 × 187 = 3179.
Mathematics
Number System
What digit x makes the number 141x divisible by 9?
A. 8
B. 4
C. 3
D. 6
Correct Answer: C
A number is divisible by 9 when its digit sum is divisible by 9. Thus 1+4+1+x must be a multiple of 9, giving x = 3.
Mathematics
Number System
Find the next number: 3, 10, 31, 94, 283, ?
A. 851
B. 849
C. 847
D. 850
Correct Answer: D
Each term is obtained by ×3 + 1. So 283 × 3 + 1 = 850.
Mathematics
Number System
Two positive integers have HCF 8 and LCM 616. What is their product?
A. 4936
B. 624
C. 4928
D. 616
Correct Answer: C
For two positive integers, product = HCF × LCM = 8 × 616 = 4928.
Mathematics
Number System
Find the next number: 21, 22, 24, 27, 31, ?
A. 37
B. 36
C. 35
D. 32
Correct Answer: B
The differences are 1, 2, 3, 4, increasing by 1. The next difference is 5, so the answer is 36.
Mathematics
Number System
Find the next term in the series: 30, 44, 60, 78, 98, ?
A. 120
B. 118
C. 122
D. 140
Correct Answer: A
The first differences are [14, 16, 18, 20]; their second difference is constant at 2. Continuing the pattern gives 120.
Mathematics
Number System
Find the next number: 5, 10, 17, 28, 41, ?
A. 60
B. 58
C. 41
D. 71
Correct Answer: B
Successive prime numbers are added: 5, 7, 11, 13, 17. Add 17 next, giving 58.
Mathematics
Number System
Find the next number: 26, 33, 44, 57, 74, ?
A. 110
B. 74
C. 95
D. 93
Correct Answer: D
Successive prime numbers are added: 7, 11, 13, 17, 19. Add 19 next, giving 93.
Mathematics
Number System
What is the greatest multiple of 17 that is less than 1965?
A. 1938
B. 1972
C. 1956
D. 1955
Correct Answer: D
1965 ÷ 17 has integer quotient 115; 17 × 115 = 1955.
Mathematics
Number System
What least number must be added to 709 so that the result is exactly divisible by 14?
A. 5
B. 19
C. 6
D. 9
Correct Answer: A
709 leaves remainder 9 on division by 14. Add 14 - 9 = 5.
Mathematics
Number System
Classify 6/18.
A. Rational
B. Whole number
C. Irrational
D. Prime number
Correct Answer: A
6/18 is a ratio of two integers with a non-zero denominator, so it is rational.
Mathematics
Number System
Find the next number: 35, 40, 47, 58, 71, ?
A. 101
B. 71
C. 88
D. 90
Correct Answer: C
Successive prime numbers are added: 5, 7, 11, 13, 17. Add 17 next, giving 88.