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40 and all its multiples...
It is: 80 and 100
They are 20, 40, 60, 80, 100.
80.
40, 80, 120, 160, 200.
40, 80, 120, 160, 200
40, 80, 120 +40 . . .
The factors of 80 are: 1, 2, 4, 5, 8, 10, 16, 20, 40, 80 Those which are multiples of 4 are: 4, 8, 16, 20, 40, 80
20, 40, 60, 80, 100, 120 * * * * * These are the first six multiples!
The Least Common Multiple (LCM) for 5 and 8 is 40.
Everything except 20, 40, 60, 80 and 100.
40, 80, 120
40, 80, 120 and so on.
No number has the multiples of 1, 2, 4, 5, 8, 10, 16, 20, 40, 80, but the number 80 (and all its multiples: 160, 240, 320, 400, ...) has them all as FACTORS.
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The first 5 multiples of 4 and 20 are 20, 40, 60, 80, 100