Is there more than one way to get 2/3/4/5 to the simplest form

Leo has b boxes of pencils. each box contains 6 pencils. he has a total of 42 pencils. the equation that represents this situation the value of b that makes the equation true the first one is b+6=42,6b=42,b=42+6,or 42b=6 the second one are 7,836 48

Sorry guys but as you have a small brain

What numbers are included in the set of integers? what numbers are not included?