Question

1. Express each number as a product of its prime factors:
2. Find the LCM and HCF of the following pairs of integers and verify that LCM X HCF=
3. Find the LCM and HCF of the following integers by applying the prime factorisation
4. Given that HCF (306, 657)=9, find LCM (306, 657).
6. Explain why 7x11x 13 + 13 and 7x6x5x4x3x2x1 +5 are composite numbers.
5. Check whether 6" can end with the digit O for any natural number n.
7. There is a circular path around a sports field. Sonia takes 18 minutes to drive one round
same point and at the same time, and go in the same direction. After how many minutes
of their
EXERCISE 1.2
(i) 140
(ii) 156
(v) 7429
product of the two numbers.
(iii) 3825
(iv) 5005
(iii) 336 and 54
method.
(i) 12, 15 and 21
(ii) 17,23 and 29
(iii) 8, 9 and 25
will they meet again at the starting point?​

Answer 1

Answer:

4)Then we will select the numbers which are common to both 306 and 657. Then we will multiply these selected numbers. The LCM of these two numbers will be a product of these selected numbers and the remaining numbers. Thus, LCM of 306 and 657 is 22338.

Answer 2