Measures of Central Tendency Mean Median Mode Range

Measures of Central Tendency Mean, Median, Mode, Range

Vocabulary Hey Diddle, the median’s the middle You add and divide for the mean The mode is the one, that you see the most And the range is the difference between

Vocabulary Mean – average Median – middle Mode – most Range – difference

Definition Range (difference) the difference between the largest and smallest numbers in the list of data

Range The difference between the lowest and highest number Test scores: 65, 73, 88, 69, 71, 78, 86, 99, 62, 77

Range Put in numeric order: 62, 65, 69, 71, 73, 77, 78, 86, 88, 99 Lowest number 62 Highest number 99 Range 99 – 62 = 37

Choose your Measure! Measures of Central Tendency

You have taken seven tests and earned the following grades: 80, 86, 81, 82, 85, 96 Mrs. Gage is going to let you choose which measure she is going to use to determine your final grade. Would you like her to use the mean, median, mode of your test grades? How do you choose?

80, 86, 81, 82, 85, 96 Put in numeric order: 80, 81, 82, 85, 86, 96 Mean: 606 / 7 = 86. 6 Median: 85 Mode: 96

Which did you choose? MODE!!

You have taken 8 tests and earned the following grades: 91, 78, 80, 90, 81, 88, 82 Would you like her to use the mean, median, mode of these test grades? How do you choose?

91, 78, 80, 90, 81, 88, 82 Put in numeric order: 78, 80, 81, 82, 88, 90, 91 Mean: 670 / 8 = 83. 75 Median: 81. 5 Mode: 80

Which did you choose? MEAN!!

These are the scores from last week's geometry test: 90, 94, 53, 68, 79, 84, 87, 72, 70, 69, 65, 89, 85, 83, 72 You earned a score of 79. Your mom asks you how you did on the test compared to the rest of the class. Calculate three measures of the average, and decide what to tell your mom

Numerical Order: 53, 65, 68, 69, 72, 72, 79, 83, 84, 85, 89, 90, 94 Mean: 1164 / 15 = 77. 6 Median: 79 Mode: 72

Suppose your test grades in American History are 80, 93, and 91. What grade do you need on your next test to have a 90 average? Equation: (80 + 93 + 91 + X) / 4 = 90 What does this represent? Missing Grade How many TOTAL Grades! What does this represent? The average you want!

Equation: (80 + 93 + 91 + X) / 4 = 90 (4) • 264 + x = 90 • (4) 4 264 + x = 360 x + 264 = 360 -264 x= 96 What does this mean?

Bowling Scores: 100, 121, 105, 113, 108, x; What do I need to bowl in the last game to have an average of 112? (100+121+105+113+108+x)/6 = 112 (6) • 547 + x = 112 • (6) 6 547 + x = 672 x + 547 = 672 -547 - 547 x = 125