Question

A car passes a landmark on a highway traveling at a constant rate of 55 kilometers per hour. One hour later, a second car passes the same landmark traveling in the same direction at 63 kilometers per hour. How much time after the second car passes the landmark will it overtake the first car?

Do not do any rounding.

Answer 1

Okay. First, think about what conditions mean that one car passes another...

Answer 2

I don't understand?

Answer 3

well their distance travelled after the landmark must be same right?

Answer 4

Yes

Answer 5

Okay so then consider that the distance is x, alright?
Then you know their speeds and the time difference. The second car starts one hour later. So, whatever time in which they reach at that same point, value of t for second car is t-1 hrs.
Now equate speed/time for both

Answer 6

I don't know how to do that. D:

Answer 7

I'm sorry, I really don't understand this. I need help.

Answer 8

Refer to the attachment from Mathematica.

Answer 9

following?

Answer 10

Yes sir/ma'am

Answer 11

Then, distance=speed*time, right?
That would mean 55*t=63*(t-1)

Answer 12

solve this for t!

Answer 13

7.875?

Answer 14

yeah, sorry but the question need t-1 right?

Answer 15

I chose t to be time elapsed for first... so 6.875 will be the answer.

Answer 16

Oh, I understand now! Thanks. I have 5 more questions like this to do and I think I can get them on my own now. :)

Answer 17

shouldn't it be `t+1` since it was an hour later?

Answer 18

`t-1` would mean the second car left an hour before the first, no?

Answer 19

I chose the other value for t for the question @Jhannybean. and no an hour late would mean lesser time elapsed right?.

Answer 20

t represents time elapsed after crossing the landmark.

Answer 21

time it takes for the first car to pass the landmark = t

time it takes for the second car to pass the landmark an hour later = t+1

Answer 22

Let t be the time to catch the first car.
55 (1 + t) = 63 t // Solve
t = 55/8 = 6.875

Answer 23

Thank you for the medal.