Question 286926
I they are traveling in opposite directions
you can add their speeds and consider one
to be stationary and the other moving
Let {{{s}}} = speed of the slower one
{{{270 = (s + s + 10)*3}}} km
{{{270 = (2s + 10)*3}}}
{{{270 = 6s + 30}}}
{{{6s = 240}}}
{{{s = 40}}}
{{{s + 10 = 50}}}
The slower boat's speed is 40 km/hr
check:
slower boat:
{{{d[s] = 40*3}}}
{{{d[s] = 120}}} km
faster boat:
{{{d[f] = 50*3}}}
{{{d[f] = 150}}}
{{{120 + 150 = 270}}}
OK