Free Factors and Multiples 02 Practice Test - 5th Grade
Question 1
___ is a pair of co-prime numbers.
SOLUTION
Solution : B
If any two numbers Highest Common Factor is 1, then they are called co-prime to each other.
HCF of 12 and 15 is 3
HCF of 7 and 15 is 1
HCF of 22 and 48 is 2
HCF of 24 and 36 is 12
Therefore 7, 15 is a pair of co-prime numbers since they have an HCF of 1.
Question 2
A factorization in which every factor is a prime number is called
SOLUTION
Solution :Prime factorization is finding the factors of a number that are all prime. The prime factors of 15 are 3 and 5.
Question 3
Which of the following is a factor pair of 24?
SOLUTION
Solution : D
4 and 6 form a factor pair of 24 as 4×6=24.
2 and 13 form a factor pair of 26 as 2×13=26.
1 and 13 form a factor pair of 13 as 1×13=13.
3 and 12 form a factor pair of 36 as 3×12=36.
Question 4
The number 7 has ___ multiples.
SOLUTION
Solution : D
To get multiples of any number, we multiply counting numbers with that number.
Since there are infinite counting numbers, multiples of any number are also infinite.
Question 5
All the multiples of 9 are also the multiples of
SOLUTION
Solution : B
9=3×3
⇒ 9 is a multiple of 3
Hence any multiple of 9 will also be a multiple of 3.
Question 6
The difference between the largest factor and the smallest factor of 100 is ___
SOLUTION
Solution : A
The smallest factor of any number is 1 and the highest factor of any number is the number itself.
Therefore, the difference between the highest and the smallest factor of 100 is, 100−1=99
Question 7
72 books were arranged equally on 8 shelves. How many books are there on each shelf?
SOLUTION
Solution : B
Number of books = 72
Number of shelves = 8
Therefore, books on each shelf = 72 divided by 8 = 9
Question 8
The product of two numbers is 228. If their HCF is 12, then what will be their LCM?
SOLUTION
Solution : C
HCF of two numbers × LCM of two numbers = Product of the two numbers
12×LCM=228
LCM =22812=19
Question 9
What is the least number that is exactly divisible by 15, 10 and 16?
SOLUTION
Solution : B
The least number that is exactly divisible by 15, 10 and 16 is the LCM of the three numbers.
215,10,16215,5,8215,5,4215,5,2315,5,155,5,11,1,1
LCM of 15, 10 and 16 =2×2×2×2×3×5=240
Question 10
What is the sum of the first 5 prime numbers?
SOLUTION
Solution : C
First five prime numbers are: 2, 3, 5, 7, 11
Product of first five prime numbers is 2+3+5+7+11=28