Preston is making cookies. He has 4 over 5 cup of flour in a bag. He then used two 1 over 10 cups of flour for his recipe. Which of the following best explains the amount of flour left in the bag?
6/10 , because 4/5-2x(1/10)=4/5-3/10
5/10 , because 4/5-2x(1/10)=4/5-3/10
6/10 , because 4/5-2x(1/10)=4/5-2/10
5/10 , because 4/5-2x(1/10)=4/5-2/10