A teacher surveyed her class after they had taken a vocabulary test. Eighteen of the students claimed they had studied at least one hour for the test. The remaining twelve students admitted that they had not studied for the test at all. The test results (expressed as a percent) for the two groups are shown below.

Studied: 87, 100, 94, 79, 92, 100, 95, 83, 89, 99, 100, 91, 89, 95, 100, 93, 96, 83
Did Not Study: 82, 72, 45, 91, 58, 83, 65, 87, 90, 77, 73, 89

Part 1: Calculate the mean of the group that studied, rounded to the nearest tenth.
Part 2: Calculate the mean absolute deviation of the group that studied, rounded to the nearest tenth.
Part 3: How many of the scores (from the group that studied) are within one mean absolute deviation of the mean.

studied mean: 90

did not study mean: 80

For the group that studied:

Mean = 92.61

Median=93.5

Mode = 100

For the group that didn't studied:

Mean = 76

Median = 79.5

Mode = No Mode

thats about all i know sorry.

b: |12 – x| ≤ 0.25

step-by-step explanation:      

let x be the possible lengths in inches, of the ribbons jaime cut.

we have been given that jaime is cutting strips of ribbon for a project. he tries to cut each piece to be 12 inches long, but sometimes he cuts it too long or too short by as much as 0.25 inch.  

we can represent this information in an inequality as:

by the definition of absolute value function we will get,

upon combining our inequalities we will get,

therefore, the inequality   describes all the possible lengths (x), in inches, of the ribbons jaime cut.

step-by-step explanation: