Hard core.....
What is sample?
Subcollection of people chosen from the population.
Jennifer knits scarves that she sells for $25 each. She sold 3 scarves on the first day, 5 on the second day, and 10 on the third day. Calculate the mean number of money she made in those three days.
$25.
What is the median of the data set? 21, 11, 15, 7, 23, 12, 19
15
How to find standard deviation on calculator?
1 Var stat
What is voluntary response sample and why is it skewed?
It is a voluntary sample and people choose to present themselves in it. It is skewed because it doesn't reflect the general population, therefore it is biased.
In her job as a barista at a coffee shop, Angela earned 3 tips of $2, 3 tips of $5, and 6 tips of $1. Calculate the mean tip.
$2.25.
What is the mode of the data set? 2, 2, 3, 4, 7, 5, 6, 4
2 and 4
What is the standard deviation of sample travel times 39 21 9 32 30 45 11 12 39
13.6
How do you denote linear correlation, what are the critical values and can it be negative?
r is used to denote linear correlation, the critical values are from -1 to -0.878 and 0.878 to 1, therefore it can be negative.
Jeremy earned grades of 87%, 96%, 70%, 90%, on four tests in one term in his math class. What was his term mark if the first test was worth 10% of his final grade, the second and third were each worth 20% and the fourth test was worth 50%?
86.9%
What is the mode of the data set? 21, 34, 50, 32, 48, 22, 56
What is no mode
How to find variance?
Square standard deviation.
How do we find relative frequency?
Class frequency/overall frequency
Janice creates pottery that she sells at craft fairs around Winnipeg. At one craft fair, she sold 5 items for $15 each, 9 items for $7.50 each, and 6 items for $12.50 each. What is the mean cost per item Janice sold?
$10.88.
What is the median of the data set? 17, 9, 22, 33, 49, 35, 61, 55
34
A set of numbers has a standard deviation of 0. What can be said about the data?
What is they are all the same.
How do we convert into z-score
(Data value-mean/standard deviation)
Jessica wrote three math tests worth 20% of her final grade. She got marks of 85%, 80%, and 91%. What mark must she get on the final exam (worth 40%) if she wants a final grade of 86%?
87%
What is the median of the data set? 27, 25, 34, 47, 34, 40, 30, 43, 47, 35, 31, 44, 47, 24, 37
35
We can approximate the standard deviation of data where the minimum number is 24 and the maximum is 30 =
1.5