At a speed of 50 miles per hour

25/36 is a little more than 2/3
the approximation costed you

instead
250/30 * 1/12 = 25/36

Thanks. Can't believe it that the answer could be so sneaky! lol

Hi Melguy,
This is how u solved right?

If a car travels for 5 hours at 50 miles per hour, it could travel a distance of

d = 5*50 =250

if 30 miles consume 1 gallon then for 250 miles it take

250/30 = 25/3 gallons

25/3 is what fraction of 12 ?

25/3 = 12*X => So, x = 25/36.

Correct me if I am wrong.[/list]

Hi Uva

Yes. You did it the right way.

Forgive me, I am still not sure how you arrive at 25/36

cazubuine wrote:Forgive me, I am still not sure how you arrive at 25/36

Which part you didn't get or the complete question itself ?

cazubuine wrote:Forgive me, I am still not sure how you arrive at 25/36

Car uses 1 gallon of has every 30 miles.
Car travelled for 5 hours at 50mph. So total = 5 x 50 = 250 miles

Amount of gas used = 250 / 30 or 25 / 3

Full tank was 12. So the amount used would be what fraction of the full tank? =

25
-----
3
---------
12
-----
1

Simplifying

25
-------
3 x 12

Another way to think about this:

If I use 1 gallon every 30 miles, my ratio of gas used to miles traveled is 1/30. So if I travel 250 miles, I start with this equation:

1/30 = x/250, or x = 25/3.

To get the fraction of a full tank, I just simplify

(25/3)/12

= (25/3) * (1/12)

= 25/36