Maths Help
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Maths Help
A father left home at 2-00am and travels @ 60miles per hour. Ten minutes later his son leave home and was travelling @80 miles per hour.
How far have the father gone at the moment his son begins his chase?
At what time will the son catch up with his father?
How far have the father gone at the moment his son begins his chase?
At what time will the son catch up with his father?
1st part, if he is travelling at 60miles per hour,he travels a mile a minute..
therefore after 10 minutes, he has done 10 miles...
If his son travels at 80 miles an hour.
80 = 60 + 20 minutes
60mph = 1 mile per minute
20 mph = 1/3 mile per minute
80 mph = 1 1/3 miles per minute, so he travels 4 miles in 3 minutes.
I;'ll get back to you with teh answer once I've drawn a diagram!
therefore after 10 minutes, he has done 10 miles...
If his son travels at 80 miles an hour.
80 = 60 + 20 minutes
60mph = 1 mile per minute
20 mph = 1/3 mile per minute
80 mph = 1 1/3 miles per minute, so he travels 4 miles in 3 minutes.
I;'ll get back to you with teh answer once I've drawn a diagram!
This is always an interesting one.
I always tend to use algebra and S=D/T
1st part is as described by yoyo123
For 2nd part:-
At the point they cross they will have travelled the same distance.
Hence, D = T x S
Therefore Tf x Sf = Ts x Ss
But because the son sets out 10 mins (or 10/60 hours) later, hence
Tf = (Ts + 10/60)
Therefore Sf x (Ts + 10/60) = Ss x Ts
And Sf = 60 and Ss = 80
Therefore 60Ts + 10 = 80Ts
or 20Ts = 10
Therefore Ts = 10/20 or 1/2 hour
I always tend to use algebra and S=D/T
1st part is as described by yoyo123
For 2nd part:-
At the point they cross they will have travelled the same distance.
Hence, D = T x S
Therefore Tf x Sf = Ts x Ss
But because the son sets out 10 mins (or 10/60 hours) later, hence
Tf = (Ts + 10/60)
Therefore Sf x (Ts + 10/60) = Ss x Ts
And Sf = 60 and Ss = 80
Therefore 60Ts + 10 = 80Ts
or 20Ts = 10
Therefore Ts = 10/20 or 1/2 hour