What's the Lowest Common Multiple (LCM) of 7 and 8?

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Answer 1 · 2018-02-01T17:10:23

56

write down the multiple of 7, n then 8. choose the one that's common and the least. :)

multiples of 7 $=>7, 14, 21, 28, 35, 42, 49, color(red)(56), 63....$
multiples of 8 $=>8, 16, 24, 32, 40, 48, color(red)(56), 64, 72....$

so the lcm, I.e. least common multiple of 7 and 8 is, 56.

Answer 2 · 2018-02-06T20:06:32

$7xx8=56$
They have no common factors apart from $1$

$7 and 8$ are consecutive numbers.

Therefore they have no common factors apart from $1$

The first time they will share a common multiple is with their own product.

$7 xx8= 56$

Looking at their prime factors:

$" "8 = " "2xx2xx2$
$" "7 = 7$

$LCM = 7 xx2xx2xx2 =56$