Page 52 - Revised Maths Wisdom Class - 6

50 MATHS

5. Express the following as sum of three odd primes:
(a) 63 (b) 95 (c) 49
6. Using division method find the prime factor of 1512:
(a) 128 and 48 (b) 24, 32 and 90

7. Find the first three common multiples of:
(a) 4 and 6 (b) 2, 3 and 4
8. Is 3551 a multiple of 53?

9. Which of the following are prime numbers
(a) 116 (b) 293 (c) 331 (d) 217
10. Using division method, Find the prime factors of the following numbers.
(a) 2121 (b) 1197 (c) 20570

VOCABULARY
VOCABULARY
Consecutive Multiple Factor Divisor Twin Applications

ACTIVITY TIMECTIVITY TIME
A

Objective: To find the Lowest Common Multiple of two numbers.
Materials Required: Graph paper/squared paper (alternatively a printout of number grid from 1 to 100 can be
used) colour pencils.
Procedure: 1. Choose any two numbers say 3 and 5.
2. Take the number grid as shown here and draw a box on multiples of 3.

3. Draw a circle on multiples of 5.

1 2 3 4 5 6 7 8 9 10

11 12 13 14 15 16 17 18 19 20
21 22 23 24 25 26 27 28 29 30

31 32 33 34 35 36 37 38 39 40

41 42 43 44 45 46 47 48 49 50

51 52 53 54 55 56 57 58 59 60
61 62 63 64 65 66 67 68 69 70

71 72 73 74 75 76 77 78 79 80

81 82 83 84 85 86 87 88 89 90
91 92 93 94 95 96 97 98 99 100

4. Find out the first number with both box and circle that is 15.

Conclusion: The Lowest Common Multiple of 3 and 5 is 15.