Question 1173675

A cabin cruiser leaves a harbour and travels south at 15km/h. One hour later a speed boat leaves the same harbour and travels on the same course at 25 km/h. How far from the harbour will the speed boat pass the cruiser?
<pre>Let distance from the harbour, be D
Then time the slower boat took to get to that point = {{{D/15}}}
And, time the faster took to get to that point = {{{D/25}}}
We then get the following TIME equation: {{{matrix(1,3, D/15, "=", D/25 + 1)}}}
5D = 3D + 75 ------ Multiplying by LCD, 75
5D - 3D = 75
2D = 75
Distance from the harbour, or {{{highlight_green(matrix(1,6, D, "=", 75/2, "=", 37.5, km))}}}