<PRE><B>Question 855535</B>
Let w = distance walked
Let c = distance cycled
:
David covers a distance of 15 km,
w + c = 15
:
partly bye foot at 6 km/h and partly by cycle at 18 km/h.
If he takes 1 hour and 10 minutes to finish the journey
write a time equation; time = dist/speed
{{{w/6}}} + {{{c/18}}} = 1{{{1/6}}} hrs
{{{w/6}}} + {{{c/18}}} = {{{7/6}}} hrs
multiply by 18 to clear the denominators
3w + c = 3(7)
3w + c = 21
 w + c = 15
------------subtract the 1st equation, eliminate c, find w
2w = 6
w = 3 km walked
:
:
You can confirm this solution, find the distance cycled and find the total time





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