Ms. Graves gave her class 12 minutes to read. Carrie read 5 1/2​ pages in that time. At what rate, in pages per hour, did Carrie read?

A

1 1/10
B

22

C

27 1/2 

D

66 

1 answer

To find Carrie's reading rate in pages per hour, we first need to convert the time from minutes to hours, then calculate the reading rate.

  1. Convert time from minutes to hours: \[ 12 \text{ minutes} = \frac{12}{60} \text{ hours} = \frac{1}{5} \text{ hours} \]

  2. Determine the number of pages read: Carrie read \(5 \frac{1}{2}\) pages, which can be converted to an improper fraction: \[ 5 \frac{1}{2} = \frac{11}{2} \text{ pages} \]

  3. Calculate the reading rate in pages per hour: The reading rate (in pages per hour) can be found using the formula: \[ \text{Rate} = \frac{\text{Pages}}{\text{Time in hours}} = \frac{\frac{11}{2} \text{ pages}}{\frac{1}{5} \text{ hours}} \]

    When dividing by a fraction, multiply by its reciprocal: \[ \text{Rate} = \frac{11}{2} \times \frac{5}{1} = \frac{11 \times 5}{2} = \frac{55}{2} \text{ pages per hour} \]

  4. Convert this to a mixed number for better understanding: \[ \frac{55}{2} = 27 \frac{1}{2} \text{ pages per hour} \]

Therefore, the rate at which Carrie read is 27 1/2 pages per hour.

The correct answer is C) 27 1/2.