A speedboat

A speedboat goes 900 km against a current of 25 km/hr. Its trip took 10 minutes longer than it would have taken to travel with the current. What is the speedboat's speed in still water?

Correct answer:

v =  520.2163 km/h

Step-by-step explanation:

s=900 km c=25 km/h Δ=10 min h=10:60  h=0.16667 h  t1 = v+cs t2 = vcs  t1 = t2  Δ v+cs = vcsΔ  s(vc)=s (v+c)Δ (vc) (v+c)  900(v25)=900 (v+25)0.16666666666667 (v25) (v+25) 0.16666666667152v245104.167=0 v1,2=±45104.166666667/0.16666666667152=±520.21630116 v1=520.21630116 v2=520.21630116  v>0  v=v1=520.2163=520.2163 km/h

Our quadratic equation calculator calculates it.

Did you find an error or inaccuracy? Feel free to write us. Thank you!

Showing 1 comment:
Ans. 190.09kph
1. the whole trip is 2 times the time plus 10mins due to counter current. (time= 2T + 10/60). time unit is in hours.
2. (900/x) is the velocity in still waters. since Distance = V*T, thus, T=D/v.
hope it can helps.

Tips for related online calculators
Are you looking for help with calculating roots of a quadratic equation?
Do you have a linear equation or system of equations and looking for its solution? Or do you have a quadratic equation?
Do you want to convert velocity (speed) units?
Do you want to convert time units like minutes to seconds?

You need to know the following knowledge to solve this word math problem:

We encourage you to watch this tutorial video on this math problem: video1

Related math problems and questions: