Question

1)Find the HCF and LCM of 16,220,140 using fundamental theorem of arithmetic.
2)Find the HCF and LCM of 404,808 using fundamental theorem of arithmetic.
3)Find the HCF and LCM of 405,150 using fundamental theorem of arithmetic.
4)Find the HCF and LCM of 164,168 using fundamental theorem of arithmetic.
5)The HCF and LCM of two numbers are 9 and 360 respectively. If one number is 45, write the other number.
6) The HCF and LCM of two numbers are 33 and 264 respectively. When the first number is completely divided by 2 the quotient is 33. Hence find the other number.
7)Find the ratio of LCM to HCF of 5,15,20.
8)Find the HCF and LCM of 60,80 and check whether product of HCF and LCM is equal to product of the numbers.
9) Three numbers are in the ratio 2:5:7. Their LCM is 490. Find the square root of the largest number.
10)Find the LCM of smallest prime and smallest odd composite natural number.​

Answer 1

Answer:

Prime factorisation of 42=2×3×7

Prime factorisation of 72=2×2×2×3×3=2

3

×3

2

∴HCF(42,72)=2×3=6

And, LCM(42,72)=2

3

×3

2

×7

1

=504