If the last digit doubled subtracted from the rest is a multiple of 7, the whole number is divisible by 7.
Any multiples of 7 are divisible by 7
They are any five multiples of 28.
Any multiples of 7 itself
Multiples of 7 include 7, 14, 21, 28, 35 and so on. For them to be common, they need to be compared to another set of multiples.Itself and any other multiples of 7
Itself and any of its multiples
There are no multiples of 7 down there, nor are there any NON-multiples of 7 . The truth is that there are no numbers at all below.
Common multiples of 7 and 4 include any multiple of 28.
7 and any multiple of 7 Any multiples of 7 that differ by 7
Any number other than multiples of 7
Itself and any other multiples of 7
Oh, dude, common multiples are just numbers that all three of these divas can divide into without any drama. So, for 2, 3, and 7, their common multiples would be like 42, 84, 126, and so on. It's like finding a party playlist that everyone can groove to without any complaints.
Multiples of 91:91 / 7 = 1391 / 13 = 77,13,91There really aren't any tricks here, just trial and errorSome multiples of 156:Because we already found the multiples of 91, and we know 156 isn't divisible by 91, let's try 13 (once again trial and error)156/13 = 122,12,13,156The answer is 13.