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## Comment on

Rani’s Average Speed## I actually solved this

## Why the weighted average

Full Distance = X + Y

[X/(X + Y)]*A + [Y/(X + Y)]*B

(XA + YB)/(X + Y)

Answer D?

## Great question!

Great question!

I'm not 100% sure, but I believe it has something to do with the fact that Weighted Averages are typically used to find an average measurement among a population of measurements (e.g, the average height among a population of males and females).

When we calculate average speed we aren't calculating an average of a number of values.

This is my initial hunch. If I think of a better response I,ll be sure to edit the above.