Final answer:
The taxi would charge $6.25 for a 3-mile trip.
Step-by-step explanation:
To calculate the total charge for a 3-mile trip in a taxi that charges $2.50 per ride plus $1.25 per mile traveled, we need to multiply the number of miles by the charge per mile and then add the flat rate charge per ride. In this case, the charge for a 3-mile trip would be $2.50 (flat rate) + ($1.25 x 3 miles) = $2.50 + $3.75 = $6.25.