Practice Example 1: Sample Data (4.1) - Standard Deviation & Variance - IB 10 Mathematics

Practise this section

10 questions

Flashcard drill
5 cards from this section. Quick, good the night before a test.
Exercise
6 questions · about 4 min · pass mark 70%. Hints available.
Sign up to start the exercise
Quiz
4 questions · about 3 min · pass mark 70%. Hints available.
Sign up to start the quiz

6 sample questions

Question 1.
Find the mean of the sample 4, 7, 7, 9, 13.
Show hintHide hint
Add the values and divide by how many there are.
Question 2.
Find the deviation of each value in 4, 7, 7, 9, 13 from the mean, and check that they add up to zero.
Show hintHide hint
Subtract the mean, 8, from each value.
3Question 3.
What is the mean of 3, 5, 7, 5, 10?
- 5
- 6
- 7
- 30
Show hintHide hint
Divide the total by the number of values.
4Question 4.
For 3, 5, 7, 5, 10, what is the sum of the squared deviations from the mean?
- 0
- 9
- 28
- 30
Show hintHide hint
Square each deviation before adding.
Question 5.
In the marks 3, 5, 7, 5, 10, the 10 is replaced by 20. Find the new mean and sample standard deviation, and comment on the effect of this one change.
Show hintHide hint
Recalculate the mean first, because every deviation depends on it.
Question 6.
A sixth mark is added to 3, 5, 7, 5, 10 and the mean stays at 6. Find the sixth mark and the new sample standard deviation.
Show hintHide hint
A value equal to the mean adds nothing to the sum of squares but increases n.

6 more questions in this section. Enroll free to practise them all.