fatihaysu wrote:
On a recent trip, Cindy drove her car 290 miles, rounded to the nearest 10 miles, and used 12 gallons of gasoline, rounded to the nearest gallon. The actual number of miles per gallon that Cindy's car got on this trip must have been between
a) 290/12.5 and 290/11.5
b) 295/12 and 285/11.5
c) 285/12 and 295/12
d) 285/12.5 and 295/11.5
e) 295/12.5 and 285/11.5
My approach is;
a)for miles x must be = 284< x < 295
b)for gasoline x must be = 11,4< x <12,5
then the answer has to be D or E
I chose E because of order like a/b = 284/11,5<x<295/12,5
Why the answer is D? And is it 700+ question?
Cindy drove her car 290 miles, rounded to the nearest 10 miles -->
\(285\leq{m}<295\);
Used 12 gallons of gasoline, rounded to the nearest gallon -->
\(11.5\leq{g}<12.5\);
Minimum Miles per gallon, m/g --> \(\frac{285}{12.5}<\frac{m}{g}<\frac{295}{11.5}\) (to get lower limit take min possible for nominator and max possible for denominator, and for upper limit take max possible for nominator and min possible for denominator).
Answer: D.
Hope it's clear.