It's 7km from Tim's house to where his grandma lives.
It's uphill on the way, so he can only travel at 14 kph but he can do 21 kph on the way back.
Tim leaves his house at 6pm.
How long can he stop a Grandma's house if wants to be home to watch his favourite TV at 7pm?
14 kph ÷ 2 = 7km
1h ÷ 2 = 30mins
21 kph ÷ 3 = 7
1h ÷ 3 = 20mins
30mins + 20mins = 50mins
1h - 50mins = 10mins
Tim can stay at Grandma's House for 10 mins until he has to go home.
Hi Elliot,
ReplyDeletethanks for sharing the problem and your working out. You have solved the problem, I think that's exactly how I would have worked it out too. Maybe you could write a similar problem and share it here, so that others can have a go at answering your problem?