How do you know?
2) Would you get to some of these numbers if you were counting in sevens from zero? Which ones?
Can you explain how you arrived at your answers?
3) Could some of these numbers be reached if you were counting in nines from zero? Which ones?
Again, how do you know?
4) Would your answers be the same if you counted in the same step sizes but down from 350 in each case?
How do you know?
If you were counting in 25s from 10, which numbers would you land on this time? How can you work this out without actually counting?