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_sophie_ | 12:17 Sun 18th Apr 2010 | Jobs & Education
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I have posted another maths question which I need help on for my final exam! Please check that out too if you can!

a) In the first stage of Marcus' journey he covered 180 miles in x hours. Find, in terms of x, his average speed.
= 180/x

b) He covered the 60 miles of the second stage of his journey in 2 hours less time than the first stage. Find an expression for his average speed for the second stage of his journey.
= 60/x-2

c) His average speed on both stages of his journey were the same. Calculate the time taken for the whole of his journey.
=> 180/x = 60/x-2
=> 180(x-2) = 60x (cross multiplied)
=> 120x = 360
=> x=3

I need help on part c). I get the first two line but can someone explan how they suddenly get 120x?! I am so confused.
LOL im so bad at maths! Sorry.. bet this is actually easy I just can't see it haha.
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Start from:
180(x-2) = 60x
Multiply out brackets
180x-360= 60x
-60x from both sides
120x-360=0
Add 360 to both sides:
120x=360
so x = 360/120 =3
Doesthis make sense, sophie? Le me know if you need clarification

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