The first 10 multiples of 75 are 75, 150, 225, 300, 375, 450, 525, 600, 675 and 750. Like any other number, there are an infinite amount of multiples of 75 that can be obtained by multiplying 75 by integers larger than 10.
A multiple of a number refers to any number that is equal or larger than that original number that has the original number as a factor. This means that if a number can be divided by the original number with no remainder, then that number is a multiple of the original number. The original number would also be considered a factor of the larger number.