So for this question, I found the average speed but i can\'t find the average ve

Question

So for this question, I found the average speed but i can't find the average velocity since i need to know the displacement, and i don't know if the graph should be drawn as a vector or as velocity-time graph.
During a triathalon an athlete cycles 40km north and then 20km west in 1hr15min4sec, runs 12km south-west in 55min38sec, and then swims 1500m east in 39min04sec. Prepare a scale drawing of the athletes path on graph paper, and determine his average speed and average velocity in m/s. On your diagram indicate the direction of the average.
So since you can only answer one question, i would ask how do you draw the diagram? because from there i think i can find the average velocity myself. Thank you.

Explanation / Answer

What I'd do is draw the vectors and then just add up the total time. Then you get the net displacement and divide it by the total time.

Total N-S movement (North is positive)= 40 - 12sin45 = 31.51km
Total W-E movement (East is positive) = -20 + 1.5 -12cos45 = -26.98
Total distance = 31.512+26.982=41.48km

=tan-1(31.51/26.98)= 49.43 degrees N of W

t=169 minutes 46 seconds = 2.83 hr

v = 41.48km/(2.83)=14.66 km/hr

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