Answer with explanation:
Time taken by Aspen to solve 25 math problems
[tex]=12 \frac{1}{2} \text{minutes}\\\\=12:30'[/tex]
Using Unitary method to solve this problem
25 math problems = [tex]\frac{25}{2} \text{minutes}[/tex]
[tex]\rightarrow \frac{25}{25} \text{Math problem}=\frac{25}{25 \times 2} \text{minute}\\\\\rightarrow 1 \text{Math Problem}}=\frac{1 \text{minute}}{2}\\\\\rightarrow 38\text{Math Problem}}=\frac{1 \text{minute}}{2}\times 38\\\\\rightarrow 38\text{Math Problem}}=19 \text{minute}}[/tex]
Option B: 19 minute
