# Playing With Numbers – Class 6.

Chapter 3 of NCERT/CBSE Class 6 Mathematics is about Playing With Numbers. Here in this lesson you can find practice problems for this chapter.

**MODEL QUESTIONS FOR CLASS 6 MATHEMATICSPlaying With Numbers – Chapter 3Choose the correct answer from the options given below:**

- Which of the following is a factor of 70?

A. 8

B. 9

C. 10 - Which of the following is a multiple of 12?

A. 12

B. 20

C. 32 - Which of the following is not a prime number?

A. 31

b. 41

c. 51 - Which is the only prime number between 90 and 100?

A. 93

B. 95

C. 97 - The HCF of two consecutive odd numbers is ————-

A. 1

B. 2

C. 3**Fill in the blanks:** - If a number has 0 in the ones place then it is divisible by ———-
- If the sum of the digits is a multiple of 3, then the number is divisible by ——
- The HCF of two consecutive even numbers is ————
- The LCM of 9 and 4 is ————-
- The HCF of 4 and 15 is ———–
**Answer the following:** - Write all factors of 50?
- Write first five multiples of 100?
- Express the following as the sum of two odd primes?

a) 74

b) 36 - Write the greatest 4- digit number and express it in terms of its prime factors.
- Using divisibility tests, determine 61809 is divisible by 11?

**ANSWERS:**

- 10
- 12
- 51
- 97
- 1
- 10
- 3
- 2
- 36
- 1
- Factor pairs are 1 x 50, 2 x 25, and 5 x 10.

So the factors are 1, 2, 5, 10, 25, and 50. - Multiples of 100 are 100, 200, 300, 400, 500…..
- a) 74 = 71 + 3

b) 36 = 23 + 13 - Greatest 4 digit number is 9999.

Its prime factors are 3 x 3 x 11 x 101. - Sum of the digits at odd places from right = 9 + 8 + 6 = 23

Sum of the digits at even places from right = 0 + 1 = 1

Difference = 23 – 1 = 22, which is divisible by 11.

Therefore, 61809 is divisible by 11.