When do we use L.C.M in a practical life question, and when do we use H.C.F ? For eg. there was 1 question in the revision paper given by my school, it had a question like 3 boys step together, their steps measure so and so and write the distance they all should cover with complete steps. And another question Two tankers contain some liquid 435lt and 482lt, find the max capacity of a tank that can measure the 2 tanks in exact no.of times . Please me as soon as possible, my exam is day after tommorow.

In the first question,you have to find the distance they all should cover with complete steps.
Hence here in the question it is written that distance should be covered with complete steps.
Now let the step measurement are x,y,z 
Hence for finding out the distance covered ,you have to find out the common multiple of x,y,z and since in the question ,we have to find the minimum distance .Hence we have to find the LCM of x,y and z


In the second question,you have to find the maximum capacity of a tank that can measure the 2 tanks in exact number of times.
Hence in the question ,it is given that tank can measure the 2 tanks in exact number of times.Hence the capacity of the required tank must be a factor of both 435  and 432  and since in the question,we have to find the maximum capacity.
Hence we have to find the HCF(highest common factor) of 435 and 432.


Note:- First question should be like this:- We have to find the minimum distance covered with complete steps

  • 0
What are you looking for?