Question 435739
Anna and Bea compete on a 100 meter race. Anna reached the finish line 5 seconds earlier than Bea. If Anna's speed is 1 m/s faster than Bea, find Bea's speed?
..
let x=Bea's speed in m/s
travel time=distance/speed
Bea's travel time-Anna's travel time=5 seconds
100/x-100/(x+1)=5
LCD:x(x+1)
100x+100-100x=5x^2+5x
5x^2+5x-100=0
x^2+x-20=0
(x+5)(x-4)=0
x=-5 (reject)
x=4 
Ans:
Bea's speed=4 m/s
Anna's speed=4+1=5 m/s