Question
A current's speed is 7 mph. A boat travels three times slower against the current that with the current. What is the speed of the boat in still water?
Answers
Answered by
GPT 3.5
Let's call the speed of the boat in still water "x" mph. Against the current, the boat would be traveling at a speed of "x - 7" mph, and with the current, the boat would be traveling at a speed of "x + 7" mph.
Given that the boat travels three times slower against the current than with the current, we can set up the equation:
x - 7 = (x + 7) / 3
Multiplying both sides of the equation by 3 to eliminate the fraction, we get:
3(x - 7) = x + 7
Expanding the left side of the equation:
3x - 21 = x + 7
Subtracting "x" from both sides:
2x - 21 = 7
Adding 21 to both sides:
2x = 28
Dividing both sides by 2:
x = 14
Therefore, the speed of the boat in still water is 14 mph.
Given that the boat travels three times slower against the current than with the current, we can set up the equation:
x - 7 = (x + 7) / 3
Multiplying both sides of the equation by 3 to eliminate the fraction, we get:
3(x - 7) = x + 7
Expanding the left side of the equation:
3x - 21 = x + 7
Subtracting "x" from both sides:
2x - 21 = 7
Adding 21 to both sides:
2x = 28
Dividing both sides by 2:
x = 14
Therefore, the speed of the boat in still water is 14 mph.