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alfers101
on a trip a family averaged 65km/hr for the first hour 50km/hr for the second hour and 58 km/hr for the third hour. what was their average speed?
a physics question @alfers101 please post this in physics section
though I will help you wait
given : 1) at t =1 hr. , average speed = 65 kmph 2) at t = 2hr. , average speed = 58 kmph so we know that: \[\large{\frac{\textbf{total distance travelled}}{\textbf{total time taken}}=\textbf{average speed}}\]
also remember that \[\huge \frac{\text{speed}_1 + \text{speed}_2}{2} \ne \text{average speed}\] just saying
thanks? u got it soo soon @alfers101 ?
no i still dont :( but i have the idea but i dont know how to answer this
oh k so what is the idea?
do you have the answer alfers101?
FIrst, find how far they drove. Use speed*time= distance they drove 65km/hr for the first hour: distance= 65*1 do the same thing for the 2nd hour (using the new speed), and the 3rd hour add up the distances now use speed*time= distance speed= distance/time distance will be the total distance time will be the total time ( 3 hours)