It is 4 tens and 3 ones. THe first number is tens, and the second is one's. The last number is ALWAYS ones. It just goes up from there as you go out. 1 0 0 ^ | Ones!!
4 tens and 3 ones Because if you count how many "10"s there are in 43 you will get 4 and then you will have 3 left which is not enough to be considered as a "10" so you have three ones