Mathematics for IGCSE & O level - Number (Section 2)

1
Which of the following is the best example of a rational number?
Відповідь
(C)
22/7
2
Which of the following numbers has the prime factorization 2 x 3 x 5 x 7?
Відповідь
(A)
210
3
What is the lowest common multiple (LCM) of 6 and 8?
Відповідь
(C)
24
4
Which number is a multiple of 7?
Відповідь
(A)
21
5
If two numbers are relatively prime, what is their HCF?
Відповідь
(B)
1
6
Which numbers are integers?
Відповідь
A
C
7
Which of the following is an irrational number?
Відповідь
(C)
π
8
Identify the correct statement:
Відповідь
(B)
All natural numbers are integers.
9
Which of these expressions results in a rational number?
Відповідь
(B)
2√2 x √2
10
What is the value of √64?
Відповідь
(C)
8
11
Which of the following expressions results in a rational number?
Відповідь
(B)
√2 x √2
12
Which number is a factor of 48, but not a factor of 36?
Відповідь
(D)
8
13
What is the reciprocal of 4?
Відповідь
(A)
1/4
14
Which of the following statements regarding the Highest Common Factor (HCF) and Lowest Common Multiple (LCM) is correct?
Відповідь
(C)
The product of HCF and LCM of two numbers equals the product of the two numbers.
15
If a = 2^2 x 3 x 5 and b = 2 x 3^2 x 7, what is the HCF of a and b?
Відповідь
(B)
12
16
What is the next prime number after 19?
Відповідь
(B)
23
17
What is the HCF of 72 and 108?
Відповідь
(C)
36
18
Which of the following is the same as 0.75?
Відповідь
(C)
3/4
19
A number is divisible by both 2 and 3. What can you conclude about the number?
Відповідь
(C)
It is divisible by 6.
20
What is the value of 3. 5 x 4 - 2?
Відповідь
(C)
14
21
What is the smallest number that has factors of 2, 3, and 5?
Відповідь
(C)
30
22
What is the value of 3^2 + 2^3?
Відповідь
(B)
17
23
Which number is a prime number?
Відповідь
(C)
17
24
Which of these numbers is both a factor of 60 and a multiple of 3?
Відповідь
(B)
6
25
What is the result of 12 ÷ (3 + 1) x 2?
Відповідь
(B)
6
26
Which of these numbers is not a factor of 27?
Відповідь
(D)
6
27
Which number below is an irrational number?
Відповідь
(C)
2.71828...
28
Which of the following statements is true?
Відповідь
(B)
All natural numbers are integers.
29
What is the reciprocal of -3?
Відповідь
(C)
-1/3
30
Which of the following is an example of a terminating decimal?
Відповідь
(C)
5.81
31
Which of the following could be written as a fraction?
Відповідь
(B)
0.333...
32
What is the value of k in 392k, given that 392k is a cube number?
Відповідь
(B)
3
33
What is the product of prime factors of 27?
Відповідь
(B)
3 x 3 x 3
34
What is the Highest Common Factor (HCF) of 50 and 64?
Відповідь
(B)
2
35
If a number is rational, then it can be expressed as:
Відповідь
(B)
A fraction a/b where a and b are integers and b ≠ 0
36
What is the product of prime factors of 72?
Відповідь
(C)
2^3 x 3^2
37
What is the LCM of 27 and 63?
Відповідь
(B)
189
38
What is the product of the prime factors of 25?
Відповідь
(B)
5 x 5
39
What is the product of prime factors of 12?
Відповідь
(C)
2 x 2 x 3
40
Which of the following can be written as a fraction?
Відповідь
(D)
0.125
41
What is the product of prime factors of 198?
Відповідь
(B)
2 x 3^2 x 11
42
What is the reciprocal of 2/3?
Відповідь
(B)
3/2
43
Which of the following are the prime factors of 100?
Відповідь
A
C
44
What is the Lowest Common Multiple (LCM) of 42 and 49?
Відповідь
(C)
294
45
What is the highest common factor (HCF) of 8 and 12?
Відповідь
(B)
4
46
What is the product of prime factors of 210?
Відповідь
(A)
2 x 3 x 5 x 7
47
What is the product of prime factors of 350?
Відповідь
(B)
2 x 5^2 x 7
48
What is the HCF of 2016 and 10584?
Відповідь
(D)
336
49
Which is the product of prime factors of 100?
Відповідь
(B)
2^2 x 5^2
50
What is the value of k in 96k, given that 96k is a square number?
Відповідь
(C)
6