HCF and LCM - 3 Speed Tricks & 10 Typical Word Problems

@11:18 Correction: 1 is not defined as a prime number, a better example of coprimes is 9 and 14.
@41:42 Answer to hungry college student problem is 142.

Mayank explains the following two key concepts to quickly and easily identify and solve all HCF and LCM problems -
1. Quickly find HCF and LCM using 3 simple tricks in this video.
2. To detect HCF and LCM word problems, use the following keywords:
LCM
1. Minimum number of days, rounds etc.
2. Least amount of time, things etc.
3. Smallest number, length, amount of time etc.
HCF
1. Maximum (possible) number of days, things etc.
2. Longest (possible) size, length, amount of time etc.

This video will be useful for students preparing for entrance exams like JEE, SAT, ACT, GATE, GMAT, GRE.
Also aspirants preparing for examinations like Bank PO, SSC, NTSE, IAS CSAT will find the concepts in this video helpful.

Chapters:
0:00 Introduction: HCF and LCM - 3 Speed Tricks & 10 Typical Word Problems
0:20 HCF and LCM Problem Finding our Way
0:29 Let’s Roll!
1:10 Recap
2:17 LCM and HCF Light Speed!! Use Divisibility Tests
4:53 LCM and HCF Light Speed!! – Eating Small Bites
8:18 LCM and HCF Light Speed!! – Going Backwards
12:01 LCM and HCF Light Speed!! – LCM and HCF of Primes (Understand)
18:03 a×b×c≠LCM(a,b,c)×HCF(a,b,c)
19:03 Applying our Knowledge
20:19 Example Problem -1
22:11 Word Problems: LCM and HCF Trigger Words Understand and Remember
23:21 Example Problem -2
25:02 Example Problem -3
27:17 Example Problem -4
28:34 Be careful when minimum or maximum are Problem -5
30:58 Be careful when minimum or maximum are for Problem -6
33:23 Let’s Understand Two Very Common Problems (7 & 8)
37:15 Grand Finale! Two Brain Teasers!! (9 & 10)
42:35 In Next Class – HCF and LCM on Problems on Remainders

#Knowledge #Distributed #Dishcloth #Quotient #Truncated #Subtract #Factors #Divisible #Identifying #Trick #Mayank #Examrace #examrace #upsc #ugcnet

[AnkitaSingh-ldth]

I AM VERY CLEAR NOW ABOUT THIS. THANK YOU SIR

[MukeshKumar-zlmm]

I DONT HAVE THE WORDS TO THANK
YOU. YOU HAVE CLEARED MY LAST 10 YEARS DOUBT .THAT I WAS FACING IN MY STUDIES

[rajashruthim]

All my doubts were cleared Sir. Literally Thank you so much Sir.

[vishnup]

simple class but very effective..I became thorough in LCM and HCF after watching this video..thank u sir...

[motherhoodclinic]

VERY NICE SIR THANK YOU .NOW IT IS EASY FOR ME TO EXPLAIN IT TO MY DAUGHTER.PLZ EXPLIN RATIOS AND PROPORTION

[chaitanyakuppili]

helpful vedio, thank u sir.
how could we find the number if the common difference is not same?
pls explain

[shaifulhoda]

thank u so much explanation very helfulll

[diptimhatre]

Sir your method of teaching is really good and it helps me alot. Thankuu.
Sir in every imp point or in question you highlight some words in that words which are highlighted by red colour is not visible. So plz use different colour. Thank uu😊😊

[pankajverma]

At a garden site, 16 Mango trees, 24 banyan trees and 28 Guava trees are to be planted in certain no of rows in such a way that each row has equal no of trees of the same species. what is the minimum number of rows that are required for this purpose

HCF(16, 24, 28) = 4
16/4=4
24/4=6
28/4=7
4 rows of mango trees
6 rows of banyan trees
7 rows of guava trees
So answer is 17
why did the find hcf not lcm

Three wheels make 60, 36 and 24 revolutions per minute. Each has a red spot on its rim, which is at the lowest position at time zero. The red spot will all be at this position again after:
A. 2 seconds B. 5 seconds C. 4 seconds D. None of these

LCM(60/60, 60/36, 60/24) = 60/12 = 5s.

how i know that at what time hcf or lcm to be use pls help

[hassansanooj]

thank you. it was really helpful to understand the core concept

[AkshayKaushalAksha_D_Nicator]

Sir, video was really helpful. Thank you for that; however, at 8.48 you mistakenly used the term 'remainder' instead of 'quotient'.

[saravanangurusamy]

Sir in the rectangle problem if 20 X 60 is given then the max length of square is 20(by hcf) and how to find the max. Number of square??

[ismailashrafi]

this video is very very useful for us....
thanks sir g

[sahilkatoch]

thanks for the explanation, ,,got the point!!!

[shashidharmuniswamy]

Is the answer for the last hungry college students question = 142?
710 = 2x5x71
426 =2x3x71
142 = 2x71
so HCF = 71x2 = 146?
Is this correct?

[awax]

Problem #6: the minimum number of squares is produced by "maximizing" the length of each square's sides, which implies an HCF(20, 50).
The number of squares then equals total area (20 x50) divided by area of one square (10 x 10) = 10 squares.

[ChinmayTerse]

Great video! Concise explanation and lots of examples beautifully explained! Thanks a lot!

[chyilingchuah]

This is helpful but please try to make this video shorter next time!

[sri]

please explain about 11 divisibility rule.with example.

[madhukareti]

TWO NUMBERS ARE IN THE RATIO OF 15:11. IF THEIR HCF IS 13, FIND THE NUMBERS? EXPLAIN