2. A car takes 7 hours 50 minute to travel 549 9/10 km.

Mathematics

1 answer:

lorasvet [3.4K]3 years ago

3 0

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

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