Answer :
we are given the expression 30 tens - 3 tens 3 tenths. In this case, a number proceeded by "tens" means that the number is multiplied by 10 while "tenths" means that the number is divided by 10. In this case, 30*10 - 3*10*3/10 equal to 300 - 9 or 291.
When I worked it out, I got this.
30 tens=300
3 tens= 30
3 tenths = .3
So 300-30.3= 269.7