Question

a perso moves with a velocity of 30 km/h 60 km/h and 90 km /h determine average speed of person

Answer 1

$average \:speed \: = \frac{30 + 60 + 90}{3} \\ \frac{180}{3} = 60km {h}^{ - 1}$
hope this will help you

Answer 2

HEYA!
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✴AVERAGE SPEED ✴
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$\frac{30 + 60 + 90}{3} \\ \\ = \frac{180}{3} \\ \\ = 60kmh {}^{ - 1}$
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