The answer is: 9 blouses.
The explanation is shown below:
1. The remainder is:
[tex]1-\frac{3}{8}=\frac{5}{8}[/tex]
2. She used [tex]\frac{2}{5}[/tex] of the remainder to buy 2 pair of pants:
[tex](\frac{5}{8})(\frac{2}{5})=\frac{1}{4}[/tex]
3. Then, she used [tex]\frac{1}{4}[/tex] of the money to buy 2 pairs of pants. For each one she used:
[tex]\frac{1}{4}[/tex]÷[tex]2[/tex]=[tex]\frac{1}{8}[/tex] of the money for a pair of pants.
4. A pair of pants costs 3 times as much as a blouse, therefore you can write the following expression:
[tex]\frac{1}{8}=3x[/tex]
Where [tex]x[/tex] is the cost of 1 blouse
5. Solve for [tex]x[/tex]:
[tex]x=\frac{1}{24}[/tex] for each blouse
6. If she used [tex]\frac{1}{24}[/tex] of the money for 1 blouse, you have the following amount of blouses bought with [tex]\frac{3}{8}[/tex] of the money:
[tex]y=\frac{\frac{3}{8}}{\frac{1}{24}}=9[/tex]
Where [tex]y[/tex] is the total number of blouses.