2.)
average velocity=(change in distance)/(change in time), in this case:
v=(549 9/10)/(7 50/60)
v=(5499/10)/(470/60)
v=(5499/10)(60/470)
v=32994/470
v=70.2 km/hr
...
picture
Make two position functions...
c=15t, and r=120-20(t-1)
c=15t, r=140-20t
They meet when c=r so:
15t=140-20t add 20t to both sides
35t=140 divide both sides by 35
t=4
So they will meet 4 hours after Cindy leaves at 1 pm, thus they meet each other at 5 pm.
check...
c=15(4)=60
r=120-20(4-1)
r=120-20(3)
r=60
