Answer:
17.5 miles per hour
Explanation:
A boat travels upstream on a Mississippi river for 3.5 hours
The return trip takes 2.5 hours
The boat travels 2 miles per hour faster downstream
Let y represent the speed that was travelled upsteam
3.5y = 2.5(y + 2)
3.5y = 2.5y + 5
3.5y - 2.5y = 5
y = 5
Therefore the distance travelled by the boat upstream can be calculated as follows
= 3.5 × 5
= 17.5 miles per hour