There are at least 2 or 3 questions on LCM and HCF in all the competitive exams. In this article, we shall provide you some of the sums related with LCM and HCF with answers at the end of the Practice set.

**Highest Common Factor** – HCF of two or more numbers is the greatest number that divides each of them exactly. The HCF of 18 and 24 shall be 6.

**Least Common Multiple** – The LCM of two or more given numbers is the least number which is exactly divisible by each of them. For example, 15 is the common multiple of 3 and 5.

**Practice Maths Paper from here**

**Practice set for LCM and HCF –**

Q. 1. What is the HCF and LCM of 4/5, 5/6 and 7/15 ?

Q. 2. How many times is the HCF of 48, 36, 72, 24 continued in their LCM ?

Q. 3. Find the least square no which is exactly divisible by 4, 5, 6, 15 and 18.

Q. 4. Find the least number which, when divided by 72, 80 and 88, leaves the remainders 52, 60 and 68 respectively.

Q. 5. Find the greatest number of 4 digits which, when divided by 2, 3, 4, 5, 6 and 7, should leave remainder 1 in each case.

Q. 6. Find the greatest possible length which can be used to measure exactly the lengths 7 m, 3 m 85 cm, 12 m 95 cm.

Q. 7. Find the greatest no of 4 digits and the least no of 5 digits that have 144 as their HCF.

**Sums for LCM and HCF Practice**

Q. 8. The sum of two numbers is 528, and their HCF is 33. How many pairs of such numbers can be formed?

Q. 9. In a school, 391 boys and 323 girls have been divided in to the largest possible equal classes, so that each class of boys numbers the same as each class of girls. What is the number of classes ?

Q. 10. What least number must be subtracted from 1294 so that the remainder, when divided by 9, 11, 13 will leave in each case the same remainder 6 ?

Answers – 1. The HCF shall be 1/30 and LCM – 140 2. LCM = 12 times of HCF 3. 180 4. 7900 5. 9661 6. 35 cm 7. 10,080 8. 4 pairs 9. 17 10. 1

sir please give the discription how answere come.