A zebra and a giraffe are having a race, 300 yards from a row of trees (the starting line) to the edge of a stream (the finish line). When they start evenly, the zebra wins the race by 50 yards.
They decide to race again, but in the second race the zebra has to start 50 yards behind the row of trees (350 yards from the finish line), while the giraffe starts at the usual starting line. The zebra and the giraffe always run at the same speeds from race to race. Who wins the second race? Explain your reasoning.
we have that
The speed is equal to divide tthe distance by the time
speed=d/t
t=d/speed
The zebra and the giraffe always run at the same speeds from race to race.
so
Race 1
Zebra ------> t=300/speed1
giraffe ----> t=(300-50)/speed2 -----> t=250/speed2
where t is the finishing time of the zebra
equate both equations
300/speed1=250/speed2
300/250=speed1/speed2
1.2=speed1/speed2
speed1=1.2speed2
that means ----> the spped of the zebra is 1.2 times the speed of the giraffe
Race 2
Zebra ----> t1=350/(1.2speed2) ------> t1=292/speed2
Giraffe ----> t2=300/speed2 ------> t2=300/speed2
compare the times
t1 < t2
that means
the zebra wins the race 2