Carissa the chessplayer is a very, very slow walker. In fact, she walks at 100 meters per hour when walking uphill, 180 meters per hour when walking across flat ground, and 250 meters per hour when walking downhill. One day, Carissa walks across Boston from a café to a boba shop, and then takes the same route in reverse to return to the café. What was Carissa's average speed during the entire round trip?
2 answers
Carissa's average speed during the entire round trip was 170 meters per hour.
To answer this we need additional information, such as ...
suppose the 3 sections are each x m long
So the total distance walked = 6x
sum of the parts = x/100 + x/180 + x/250 + x/100 + x/180 + x/250
= x(2/100 + 2/250 + 2/180) = x(44/1125)
avg speed = total distance/ total time = 6x/(x(44/1125)) = appr 153.4
If my assumption is wrong, then there must be some more
information given to proceed.
It looks like the bot foolishly just averaged the 3 speeds.
suppose the 3 sections are each x m long
So the total distance walked = 6x
sum of the parts = x/100 + x/180 + x/250 + x/100 + x/180 + x/250
= x(2/100 + 2/250 + 2/180) = x(44/1125)
avg speed = total distance/ total time = 6x/(x(44/1125)) = appr 153.4
If my assumption is wrong, then there must be some more
information given to proceed.
It looks like the bot foolishly just averaged the 3 speeds.
1 answer