Question

Ana completed of her homework assignment. Her assignment contains 30 math problems. How many problems does Ana still need to complete

Answer 1

100% Means that it is the total. So You need to find 40% of the total homework she did. So since 100% is the total which is 30 pages.
40% will be 60% LESS than the total that she did. 
1=100% So since 60% is smaller than 1 it will be .60 don't forget the decimal.
You will have to do some math but 
.60 * 30=?

Answer 2

You would do .40 times 30. I got 12 questions