A number x is at least -10: X ≥ -10
X is *at least* -10, meaning that it will either be that or something greater.
Twice a number y is more than 5/2:
2y > 5/2
Two times y is the same as writing 2y. It says that this is greater than 5/2, thus the greater than sign.
Hope this is right and it helps :)
