Stickers are sold in packages of 15 sheets. if there are 20 students in the class, how many packages of stickers should the teacher buy so that every student gets the same amount of sheets, with none left over? 3 packages 4 packages 6 packages 10 packages (for my younger sister.)

It would be 4 it would be 4 packages

The first one, i believe, would be correct. all the others have one thing in common, and that's that they have repeating numbers. in the second one, x and y have repeating 6's and 3's, and in the third, x and y have repeating 6's as well. in the last one, there are repeating 3's. the first one has no repeating numbers.