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Math Gym
Number Theory Guide

Number Theory Level 21: LCM (<= 60). LCM through GCD.

1. Find GCD

1. Find GCD
Use the pair product divided by their GCD.

Find the shared factor first.

GCD = 15.

2. Product divided by GCD

2. Product divided by GCD
Find GCD

Multiply the pair, then divide by their GCD.

45 x 60 / 15.

3. Read LCM

3. Read LCM
Find GCD
Product divided by GCD

Read the least common multiple.

LCM = 180.