The river boat paddled upstream at 12km/h, stopped for 2 h of sightseeing, and paddled back at 18km/h. How far upstream did the boat travel if the total time for the trip, including the stop, was 7h?
Please help me, the answer is 36 km but i have no idea how to set it up
Let D be the distance travelled. The total time moving was 7 - 2 = 5 hours.
Realize that time time spent travelling in one direction is D/V, where V is the speed.
Here is what you know:
D/12 + D/18 = 5 hours
Create a common denominator.
(3D + 2D)/36 = 5
5D/36 = 5
D = 36 km
To find the distance traveled upstream by the river boat, you can use the formula:
Distance = Speed × Time
Let's break down the information given in the problem:
1. The boat paddled upstream at a speed of 12 km/h.
2. The boat stopped for 2 hours of sightseeing.
3. The boat paddled back downstream at a speed of 18 km/h.
4. The total time for the trip, including the stop, was 7 hours.
Now, let's calculate the distance the boat traveled upstream.
First, we need to determine the time spent traveling upstream. Since the boat spent 2 hours sightseeing, the remaining time for paddling upstream and downstream is 7 hours - 2 hours = 5 hours.
Now, let's consider the time spent paddling upstream and downstream separately.
Time spent traveling upstream = Time for the trip - Time spent sightseeing = 5 hours
Using the formula Distance = Speed × Time, we can calculate the distance traveled upstream:
Distance traveled upstream = Speed upstream × Time upstream
= 12 km/h × 5 hours
= 60 km
Therefore, the boat traveled 60 km upstream.