Hello! This is how you would skip count in those range of numbers: 350, 340, 330, 320, 310, 300, 290, 280, 270, 260, 250, 240. If you notice a pattern, the number ends at a zero, and the number in the tens place coulda backwards from 9 to 0 and back again. It would be vice versatile counting forward, but the number would still end in a zero.
