Standard deviation and spread

Measure how far data typically sits from the mean and compare two data sets' spread.

Standards:S-ID.A.2

Try it: three questions

Real questions from the practice bank. Tap an answer to check it.

Question 1 of 3

The five test scores for a group of students are: 72, 78, 85, 91, and 94. Find the standard deviation (rounded to the nearest whole number).

Question 2 of 3

A teacher recorded the number of days absent for 5 students: 2, 5, 3, 7, 8. Find the standard deviation (to the nearest tenth).

Question 3 of 3

Five workers recorded their hourly wages (in dollars): 14, 18, 16, 22, 20. Find the standard deviation of the wages, rounded to the nearest tenth.

How this fits in

Standard deviation and spread is one skill in the Statistics & Probability unit. Students read the unit lesson, then earn a bronze, silver, or gold medal on their last 10 answers. Medals never go down. A mastered unit comes back for review after 1, 3, 7, 16, and 35 days so it stays learned.

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