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Time and Distance question - CLEP101 - 08-26-2016
Car "A" is traveling at 50 miles an hour.
Car "B" is traveling at 51 miles an hour.
Car "B" is 1 mile behind care "A".
How much time will it take for car B to be even with Car A at the current speed.
How many miles will be traveled before car B will be even with Car A at the current speed.
What are the answers, but also what is the formula to get the answers?
Thanks in advance.
Time and Distance question - bluebooger - 08-27-2016
been awhile since I've done this so I may be doing it wrong, but this is what I think
the equation of a line is
y = mx + b
where m is the slope and b is the y intercept
on the graph x is the hours and y is the miles
why ?
because the speed is
miles
-----
hour
and slope is
change in y
-----------
change in x
so miles must be y and hour must be x
the equation for car A is
y = mx + b
y = 50x + 1
we use 1 for the y intercept because car A has a one mile headstart
so its starting point is not at the origin, but one mile ahead
the equation for car B is
y = 51x + 0
or
y = 51x
we use 0 for the y intercept because car B is starting at point zero
so if y = 51x in the 2nd equation, then substitute 51x for y in the first equation
51x = 50x + 1
subtract 50x from both sides
1x = 1
divide both sides by 1
x = 1
x is one so in one hour B catches up with A
now watch somebody smart come along and show how this is completely wrong
Time and Distance question - Flelm - 08-27-2016
It's right, but could be done without the line stuff.
distance = time * velocity
Car A: x = t * 51
Car B: x - 1 = t * 50
(Car B travels 1 mile less in the same amount of time)
Two variables, two equations. You can do a number of solving methods, but I'll just substitute.
(t*51) - 1 = t*50
t-1 = 0
t = 1
Time is 1 hour.
To find the distance, use t in either of the above equations.
x = t * 51
x = 1 * 51
x = 51
51 Miles.
Time and Distance question - CLEP101 - 09-12-2016
After reading both your posts I realized that I really really hate math. I don't know why that equation was bothering me, but it was and I couldn't get to the answer. Thanks to the both of you for helping me out.
RE: Time and Distance question - slefoll7 - 03-22-2018
It is way easier than that. Car B will take 60 minutes to catch up with car A, because it is going 1 mph faster. The absolute speed of each car does not matter, only the relative speed. Car B will also go 51 miles in that 60 minutes, because that is how fast he is going. Car A will go 50 miles, because he started 1 mile ahead of car B. No need for any equations or anything.
RE: Time and Distance question - bluebooger - 03-22-2018
(03-22-2018, 09:54 AM)slefoll7 Wrote: It is way easier than that. ...
yeah, but you had almost 2 years to think about it