the histogram shows the number of hours that students in mrs. cs class slept last night. 1. how many…

Explanation:

Step1: Identify relevant intervals for 1st question

For students who slept at least 8 hours, we consider intervals 8 - 11 and 12 - 15.

Step2: Read frequencies from histogram

From the histogram, frequency of 8 - 11 hours is 10 and of 12 - 15 hours is 4.

Step3: Calculate total for 1st question

Total number of students who slept at least 8 hours is $10 + 4=14$.

Step4: Identify relevant intervals for 2nd question

For students who slept less than 12 hours, we consider intervals 0 - 3, 4 - 7 and 8 - 11.

Step5: Read frequencies from histogram

Frequency of 0 - 3 hours is 2, of 4 - 7 hours is 12 and of 8 - 11 hours is 10.

Step6: Calculate total for 2nd question

Total number of students who slept less than 12 hours is $2+12 + 10=24$.

Answer:

1. 14
2. 24