Respuesta :
Answer:
2.1429 or 2 and 1/7
Step-by-step explanation:
Time = time
12/(15+c) = 9/(15-c)
12(15-c) = 9(15+c)
12*15 - 12c = 9*15 + 9c
21c = 3*15
c = 3*15/21
c = 45/21 = 2.1429..(speed of the current)
Downstream Info;
distance = 12 miles; rate = 15+c mph ; time = d/r = 12/(15+c) hrs.
Upstream Info:
distance = 9 miles ; rate = 15-c mph ; time = d/r = 9/(15-c) hrs.
The rate of current is 1.6.
Given that,
A boat takes 2 hours to travel 15 miles upriver against the current.
If the rate of the boat in still water is 13 miles per hour,
We have to find,
What is the rate of current?
According to the question,
A boat takes 2 hours to travel 15 miles upriver against the current.
Then,
The speed of the boat is determined by,
[tex]\rm Speed \ of \ boat = \dfrac{Distance}{Time}\\\\ Speed \ of \ boat = \dfrac{15}{2}\\\\ Speed \ of \ boat = 7.5 \ miles \ per \ hour[/tex]
Since the boat in still water can travel at 13 miles per hour, it means the current subtracts its speed from the speed of the boat.
Therefore,
The rate of current is,
[tex]= \dfrac{12}{7.5}\\\\= 1.6[/tex]
Hence, The required rate of current is 1.6.
For more details refer to the link given below.
https://brainly.com/question/5898472
