Free LCM Calculator determines the least common multiple (LCM) between 9 and 21 the smallest integer that is 63 that is divisible by both numbers. Least Common Multiple (LCM) of 9 and 21 is 63.
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Prime Factorization of 21.
3 21
7 7
1
-3x4.5=13.5. 4.5x0.5=2.25
-13.50
+2.25
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15.75 pints
Your subtracting 3x from 5x: 5x-3x
This is so you only have a variable on one side
The length of the race is 5 kilometers.
5 kilometers equals 5000 meters.
Since Lana's avarege step length is about 0.5 meters, we need to divide 5000 by 0.5

Hence, Lana needs to take about
10000 steps.
It has 4 extinct variables in the equation.