[Math] Two ships leaving a port at different times and different speeds. When do they meet

algebra-precalculus

Can someone please show me the working out to this word problem I have the answer but have no clue how to do the working out.

At noon ship A leaves port steaming at 8 knots 2 hours later ship B leaves same port on the same course steaming at 12 knots.

How far from port will ship B overtake ship A? Answer(48 miles apart)

Show me the working out please.

Best Answer

First A goes 16 miles. Then B leaves, it takes some time to overtake A, let's say time $t$. In this time A travels $8t$ miles and B $12t$ miles. Given these we have that

$$12t = 16 + 8t$$ that is $t=4$. Hence the distance is $12t = 48$.