To find the amount of income tax Al needs to pay, you can use the following formula:
\[ \text{Income Tax} = \text{Income} \times \text{Tax Rate} \]
- Al's weekly income is $400.
- His tax rate is 13%, which can be expressed as a decimal (0.13).
Now, calculate the income tax:
\[ \text{Income Tax} = 400 \times 0.13 = 52 \]
So, Al needs to pay $52 in income tax each week.