Sup Forums can't solve this
An old car has to travel a 2-mile route, uphill and down. Because it is so old, the car can climb the first mile - the ascent - no faster than an average speed of 15mi/h. How fast does the car have to travel the second mile - on the descent it can go faster, of course - in order to achieve an average speed of 30 mi/h for the trip.
wtf is a mi
how much is that in real units
A mile. That's not important though.
>do my homework for me
>How fast does the car have to travel the second mile - on the descent it can go faster, of course - in order to achieve an average speed of 30 mi/h for the trip.
Not as fast as my finger moves to report a thread that doesn't belong on this board. Do your own homework kid. Sage.
Bump
5
Wow I'm a retard
You can't average speeds like that
>Deleting posts on an ANONYMOUS forum
>mi/h
i was ashamed of my answer
Install gentoo
Total:
Average speed = Trip distance / Trip time
Trip distance = 2 mi
Average speed = 30 mi/h
→ Trip time = 2 mi / 30 mi/h = 1/15 h = 4 minutes
First half:
Average speed = 15 mi/h
Trip distance = 1 mi
→ Trip trim = 1 mi / 15 mi/h = 1/15 h = 4 minutes
This leaves us with a budget of 0 minutes to spend on the second half of the trip to stay within the required total time.
In other words, we need to cover 1 mile in 0 seconds, which is physically impossible assuming the universe is still sane. If you absolutely want an answer, it would be “infinitely fast”.
Wrong
Average speed = (ascent speed + descent speed) / 2
30 = (15 + X) / 2
X = 45
speed is averaged over time not over distance, nigger
30 mi/h = (15 mi/h * ta + x mi/h * td) / (ta + td)
ta = time to ascend = 1 mile / 15 mi/h
td = time to descend = 1 mile / x mi/h
Here's your free reply
using a far less mathematically sound method I've found that it does seem that as you increase the speed on the descent the average tends infinitely closer to 30, but never reaches it
magic
>doesn't matter how well you maintain your car, if it's old it will always be slow
Sometimes normie logic triggers me so fucking much
given S,s=S/n,, find , i!=j
t_j=s/ => =S/(s/u1+s/u2)
30=2/(1/15+1/x)=30x/(15+x) => x=\infty
good work hiding the known a+x=x problem
post it on /sci/ next
This
You wanna tell me how many stones the car weights?
fuck off hans
I got the same result. If you put it all in a single formula, which outputs the result, you get 1/0 which is impossible. This isn't limit math. 1/0 is impossible.
The lesson to learn here is that op is a faggot.
That's impossible, the speed would have to be infinite, as in the car would have to instantaneously teleport to the destination from the top of the hill?
Why? Because travelling 2 miles at 30mph takes the same time as travelling 1 mile at 15mph, as such the car has already spent that time going uphill. No matter how fast the car drives down hill, the total time the entire drive takes is going to be greater than the time required for a 30mph average, as such it is impossible to actually reach that average, it will always be lower since a car cannot drive at infinite speed/teleport.
how u know my name?