CSAT Practice Questions – HCF and LCM

1. What is the largest number less than 1000 that when divided by any of the numbers 5, 8, 12 and 15 leaves a remainder of 3?

2. If the H.C.F. and L.C.M. of two numbers are 21 and 84 respectively and the ratio of numbers is 1:4, then the larger number in these two numbers will be

3. A shopkeeper has three different kinds of rice – 40Kg, 64 kg and 72 Kg. Find the minimum number of equal capacity bags required to store the rice without mixing provided that each bag is completely filled.

4. In a large school auditorium, the students are made to sit to watch the programmes. If the teachers make a row of students of 16 each, there will be 12 students left. If they make rows of 24 each, then there will be 20 students left, if they make rows of 25 each, there will be 21 students left and if they make rows of 30 each, there will be 26 students left. What is the minimum number of students present in the school?

5. Find the highest four-digit number that is divisible by each of the numbers 24, 36, 45 and 60

6. Three company of soldiers containing 120, 192, and 144 soldiers are to be broken down into smaller groups such that each group contains soldiers from one company only and all groups have equal number of soldiers. What is the least number of groups formed?

7. A bell rings every 8 minutes. A second bell rings every 6 minutes. A third bell rings every 9 minutes. If all the three bells ring at same time at 9 o’ clock in the morning, after how much minutes will they all ring together?