Mathematics for IGCSE & O level - Number (Section 1)
1
Which of the following is a composite number?
پاسخ دهید
(D)
12
2
Identify a pair of numbers where their HCF is 1.
پاسخ دهید
(C)
7 and 10
3
What is the reciprocal of 1/5?
پاسخ دهید
(B)
5
4
What is the simplified fraction for 0.5?
پاسخ دهید
(A)
1/2
5
What are the prime factors of 42?
پاسخ دهید
(A)
2, 3, 7
6
Which of the following is a prime number?
پاسخ دهید
(C)
23
7
Which statement is true about the reciprocal of a number?
پاسخ دهید
(B)
The reciprocal of a whole number is always a fraction.
8
Which of the following is the same as 0.666...
پاسخ دهید
(B)
2/3
9
Which of the following statements are true regarding the highest common factor (HCF)?
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A
B
D
10
Which of the following are rational numbers?
پاسخ دهید
A
C
D
11
A rectangle has dimensions 240 mm by 204 mm. What is the largest possible side length for identical squares that can cover the rectangle completely?
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(B)
12 mm
12
Which of these is a correct description of a rational number?
پاسخ دهید
(B)
A number that can be expressed as a terminating or recurring decimal.
13
Which of the following is a common factor of 18 and 24?
پاسخ دهید
(C)
3
14
What is the HCF of 12 and 15?
پاسخ دهید
(B)
3
15
Which of the following is equivalent to 0. 25?
پاسخ دهید
(C)
1/4
16
Which of the following is NOT a rational number?
پاسخ دهید
(C)
√2
17
What is the reciprocal of -2?
پاسخ دهید
(B)
-1/2
18
The prime factorization of 120 is 2^3 x 3 x 5. Based on this, which of the following is a factor of 120?
پاسخ دهید
(C)
6
19
What are the prime factors of 28?
پاسخ دهید
(B)
2, 2, 7
20
What are the prime factors of 18?
پاسخ دهید
(B)
2, 3, 3
21
What is the LCM of 8 and 10?
پاسخ دهید
(B)
40
22
What is the next number in the sequence: 2, 3, 5, 7, ...?
پاسخ دهید
(D)
11
23
The HCF of two numbers is 7, and the LCM is 42. If one of the numbers is 14, what is the other number?
پاسخ دهید
(C)
21
24
What type of number is √16?
پاسخ دهید
(B)
Integer
25
Which statement about prime numbers is correct?
پاسخ دهید
(C)
There are infinitely many prime numbers.
26
Which of the following numbers is NOT a factor of 36?
پاسخ دهید
(D)
11
27
What is 5^2 - 3^2?
پاسخ دهید
(B)
16
28
What is the LCM of 15 and 20?
پاسخ دهید
(C)
60
29
What are the first four prime numbers?
پاسخ دهید
(B)
2, 3, 5, 7
30
What is the lowest common multiple (LCM) of 4 and 6?
پاسخ دهید
(B)
12
31
The HCF of two numbers is 5. The LCM of the same two numbers is 60. If one of the numbers is 15, what is the other number?
پاسخ دهید
(A)
10
32
What is the prime factorization of 50?
پاسخ دهید
(B)
2 x 5^2
33
What is the square root of 144?
پاسخ دهید
(B)
12
34
If a bus leaves a station every 40 minutes and a train leaves the same station every 45 minutes, at what time will they next leave the station together, assuming they both left the station at 7:00 am?
پاسخ دهید
(A)
10:00 am
35
What is the value of √81?
پاسخ دهید
(B)
9
36
What is the HCF of 16 and 24?
پاسخ دهید
(C)
8
37
What is the highest common factor (HCF) of 24 and 36?
پاسخ دهید
(B)
12
38
The HCF of two numbers is 3. The LCM of the same two numbers is 18. If one number is 6, what is the other number?
پاسخ دهید
(C)
9
39
What is the product of the prime factors of 30?
پاسخ دهید
(B)
30
40
What is the prime factorization of 72?
پاسخ دهید
(C)
2^3 x 3^2
41
Which number has the prime factors 2, 3, and 5?
پاسخ دهید
(C)
30
42
Which of the following is an example of a recurring decimal?
پاسخ دهید
(B)
0.333...
43
Two lighthouses flash at intervals of 22 seconds and 16 seconds, respectively. If they flash together at 10:00 PM, when will they next flash together?
پاسخ دهید
(B)
10:04 PM
44
Which of the following sets of numbers are all natural numbers?
پاسخ دهید
(B)
1, 2, 3, 4
45
Which of the following is NOT a property of prime numbers?
پاسخ دهید
(C)
They are all odd numbers.
46
What is the reciprocal of 2/3?
پاسخ دهید
(C)
3/2
47
What is the name for a number that cannot be written as a fraction?
پاسخ دهید
(C)
Irrational number
48
Which of the following numbers is NOT a natural number?
پاسخ دهید
(A)
0
49
Which set of numbers are all integers?
پاسخ دهید
(B)
-3, 0, 5, 9
50
If the LCM of two numbers is 36 and their HCF is 6, which of the following pairs could be the two numbers?
