A number which has only two factors, 1 and the number itself, is called a prime number.
Ajay : What do we call numbers like 4, 6 and 16 which have more than two factors?
Dada : Numbers like 4, 6 and 16 are called composite numbers.
A number which has more than two factors is called a composite number.
Dada : Think carefully and tell me whether 1 is a prime or composite number.
Ajay : The number 1 has only one factor, 1 itself, so I can’t answer your question.
Dada : You’re right. 1 is considered neither a prime number nor a composite number.
1 is a number which is neither prime nor composite.
Multiples and Factors Problem Set 33 Additional Important Questions and Answers
Question 1.
Write five three-digit numbers that are multiples of 3.
Answer:
102, 105, 108, 111, 114.
Question 2.
Write five two-digit numbers that are multiples of 7.
Answer:
14, 21, 28, 35, 42
Question 3.
Write five three-digit numbers that are multiples of 4.
Answer:
112, 116, 120, 124, 128.
Question 4.
Write 5 numbers that are multiples of 3 as well as 5.
Answer:
3 as well as 5 means 3 and 5. i.e. multiples of 15.
They are 15, 30, 45, 60, 75.
Question 5.
A string is 4 metres long. Can we cut it into 50 cm pieces and have nothing left over?
Answer:
4 metres = 400 cm.
We can cut it into 50 cm pieces.
Since 400 is exactly divisible by 50.
That is 400 is multiple of 50 400 + 50 = 8
We will get 8 pieces. Nothing is left over.
Question 6.
A paper Is 2 metres long. I need 8 pieces of paper each 30 cm long. How many centimetres shorter is the paper than the length I need?
Answer:
A piece of 30 cm, so for 8 pieces paper needed is 30 x 8 = 240 cm.
But paper is 2 metre = 2 x 100 = 200 cm long.
So paper is shorter by 240 – 200 = 40 cm
Question 7.
If the number given in the table is divisible by the given divisor, put P in the box. If it is not divisible by the divisor, put in the box.
Answer: