To calculate the sales tax Sally will have to pay for the snow blower, you can use the following formula:
\[ \text{Sales Tax} = \text{Price} \times \text{Sales Tax Rate} \]
In this case, the price is $349.99 and the sales tax rate is 7.5% (which is 0.075 when converted to decimal form).
Now, calculate the sales tax:
\[ \text{Sales Tax} = 349.99 \times 0.075 = 26.24925 \]
Now round this amount to the nearest hundredth:
\[ \text{Sales Tax} \approx 26.25 \]
So, Sally will have to pay approximately $26.25 in sales tax.