1.
Common factors of 15 and 25 is ......
Correct Answer
C. 5
Explanation
The common factors of 15 and 25 are the numbers that can divide both 15 and 25 without leaving a remainder. In this case, the only number that satisfies this condition is 5. Therefore, 5 is the correct answer.
2.
- If a number is divisible two co-prime numbers than it is divisible by their
Correct Answer
C. Product also
Explanation
If a number is divisible by two co-prime numbers, it means that it can be evenly divided by both of those numbers without leaving a remainder. Since the numbers are co-prime, their only common factor is 1. Therefore, the only way for the given number to be divisible by both co-prime numbers is if it is also divisible by their product.
3.
- The exact divisor of number 9 is
Correct Answer
B. 3
Explanation
The number 9 can only be divided exactly by the number 3.
4.
- Which number is factor of every number
Correct Answer
A. 1
Explanation
The number 1 is a factor of every number because it divides every number without leaving a remainder.
5.
Numbers of factors of given number are
Correct Answer
C. Finite
Explanation
The given question is asking about the number of factors of a given number. The correct answer is "finite". This means that the number of factors for the given number is limited and not infinite. Every number has a finite number of factors, including 1 and the number itself.
6.
- The numbers of multiples of given number are
Correct Answer
D. Infinite
Explanation
The given question asks for the number of multiples of a given number. The answer is "infinite" because any number multiplied by an integer will result in a multiple of that number. Since there are an infinite number of integers, there will also be an infinite number of multiples for any given number.
7.
- Every number is multiple of
Correct Answer
A. 1
Explanation
Every number is a multiple of 1 because any number multiplied by 1 equals itself. Therefore, 1 is a factor of every number.
8.
A number for which sum of all its factors is equal to twice number is called
Correct Answer
A. Perfect number
Explanation
A perfect number is a number for which the sum of all its factors (excluding itself) is equal to twice the number. In other words, if we add up all the numbers that divide evenly into the given number (excluding the number itself), the sum would be equal to twice the given number.
9.
How many factors does 36 has
Correct Answer
B. 9
Explanation
The number 36 has a total of 9 factors. These factors are 1, 2, 3, 4, 6, 9, 12, 18, and 36. To find the factors, we divide 36 by different numbers and check if the division is exact or not. If it is, then the divisor is a factor of 36. In this case, we can see that 36 can be divided by 1, 2, 3, 4, 6, 9, 12, 18, and 36 without leaving any remainder, thus giving us a total of 9 factors.
10.
- The numbers having only two factors are called
Correct Answer
C. Prime
Explanation
Prime numbers are the numbers that have only two factors, 1 and the number itself. They cannot be divided evenly by any other number. In contrast, composite numbers have more than two factors. Therefore, the correct answer is "Prime."