Question 1041198
If v=d/t; then t=d/v. Since we know Jenny traveled 5 kilometers both ways; let n be her walking speed. So
5/n+5/(n+10)=4/3 hours
15/n+15/(n+10)=4
15(n+10)+15n=4(nē+10n)
30n+150=4nē+40n
4nē+10n-150=0
Using the quadratic formula, we get
n=5 or -7.5
So her speed on foot was 5 kmh, and on bike it was 15 kmh. ☺☺☺☺