H.C.F & L.C.M. of Numbers Questions and Answers

The least number which when divided by 5, 6 , 7 and 8 leaves a remainder 3, but when divided by 9 leaves no remainder, is:

A, B and C start at the same time in the same direction to run around a circular stadium. A completes a round in 252 seconds, B in 308 seconds and c in 198 seconds, all starting at the same point. After what time will they again at the starting point ?

The H.C.F. of two numbers is 11 and their L.C.M. is 7700. If one of the numbers is 275, then the other is:

What will be the least number which when doubled will be exactly divisible by 12, 18, 21 and 30 ?

The smallest number which when diminished by 7, is divisible 12, 16, 18, 21 and 28 is:

252 can be expressed as a product of primes as:

The greatest possible length which can be used to measure exactly the lengths 7 m, 3 m 85 cm, 12 m 95 cm is:

Three numbers which are co-prime to each other are such that the product of the first two is 551 and that of the last two is 1073. The sum of the three numbers is:

Find the highest common factor of 36 and 84.

Which of the following fraction is the largest ?