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Course: PACE Math (SOE Punjab) > Unit 1

Lesson 8: Liftoff: Relationship between HCF and LCM
Math
PACE Math (SOE Punjab)
Factors and multiples
Liftoff: Relationship between HCF and LCM
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HCF and LCM word problems: Level 2

Google Classroom

Problem

Ram, Shyam, Ghanshyam and Baburam are brothers who clean their rooms according to the following schedule:
  • Ram cleans his room every third day.
  • Shyam cleans his room every seventh day.
  • Ghanshyam cleans his room every 30th day.
  • Baburam cleans his room once in 120 days. (Dirty, eh!?)
Today they are all cleaning their room.
In how many minimum days from today will all of them be cleaning their room on the same day?
  • Your answer should be
  • an integer, like 6
  • a simplified proper fraction, like 3/5
  • a simplified improper fraction, like 7/4
  • a mixed number, like 1 3/4
  • an exact decimal, like 0.75
  • a multiple of pi, like 12 pi or 2/3 pi
days