Math reasoning exercise set 7

When to use HCF when to use LCM

There are various real-life applications of LCM and HCF. The best way to understand these and grasp the concept of LCM and HCF is to learn via examples.

So let us take a look at a few examples which will help you understand LCM and HCF. H.C.F. :

We can use the H.C.F: 

•  To split things into smaller sections
• To equally distribute 2 or more sets of items into their largest grouping
• To figure out how many people we can invite
• To arrange something into rows or groups

We find L.C.M:

• In scenarios where an event is or will be repeating over and over
• To purchase or get multiple items in order to have enough.
• To figure out when something will happen again at the same time

Lets try this question

Area of 3 rectangular fields are 288, 408 and 552 sqcms respectively. A farmer decides to divide the field into blocks with same area. Find the minimum number of blocks. If the length of each block is 4cms. Find the breadth?

Solution:

Here we are dividing the blocks into smaller parts. 

We need to get smaller parts.. hence HCF..

HCF of 288,408,552 =24

LXB =24

B =6