If Denny has already walked 1800 m, How many minutes will it take for John to catch up with Denny by bike?

Question

Denny and John leave a station at different times, with both travelling in the same direction. Denny walks 60 metres per minute, and John cycles 210 metres per mintute

 

If Denny has already walked 1800 m, How many minutes will it take for John to catch up with Denny by bike??

 

 

 

 

Answer 1

If the assumption is that Denny is still walking at 60m/minute in the same direction that John is trying to catch up by bike at 210m/minute, then your equation needs to be set up as 210x = 60x+1800.

 

The x is the amount of time it will take John to catch up and the 60x allows for Denny to continue walking.  Simply subtract 60x from both sides giving you 150x = 1800. (ans 12 minutes).

 

If you plug in 12 on both sides of the equation you'll see the numbers match.  In fact, if the question asked at what distance would John catch up to Denny, you'd be able to find that out as well.

 

Cheers!