Amil and Abe rode in a bike-a-thon. Abe rode for 77 minutes at a faster rate per mile then Amil. Amil rode 15 miles in 55 minutes. Find Amil's unit rate. Then explain how you could use it to find a possible unit rate for Abe.

Scores on a university exam are normally distributed with a mean of 78 and a standard deviation of 8. the professor teaching the class declares that a score of 70 or higher is required for a grade of at least “c.” using the 68-95-99.7 rule, what percentage of students failed to earn a grade of at least “c”?