Question

What is the mean of Variable B? Express answer to one decimal place.


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Answer 1

Mean is the average.

Answer 2

Yes I know that and I know how to get the mean but what does it mean by 'decimal"?

Answer 3

And I'm confused as to how I'd list the numbers.

Answer 4

I see that Variable B takes on 8 values in this chart.

Add together all 8 values. Then divide the sum by 8, the number of data points.
What do you get?

Look: 8/3 is 2 2/3, or about 2.6666. That's a "decimal" answer

9/3 is 3. That's an integer answer.

Answer 5

Look at the graph. I see 8 points there; do you? Read off the y-value of each point.
List those 8 values. Add them together. Divide the sum by 8. That's your average for Variable B.

Answer 6

@mathmale Sorry, I'm a bit dumb. What are the values/numbers exactly?

Answer 7

And how do you find them in this kind of graph?

Answer 8

Like say if the numbers were 1, 2, 5, 6, 7, 7, 8 or something like that, I get how you add everything together and divide by the number of numbers, for this example would be 7. But how would you get those numbers in this kind of graph?

Answer 9

Do you see the y-value 6?
Follow the horiz. line thru y=6. This line intersects a point (black dot). We say that "Variable B includes the vaue 6 because of that dot.

Alternatively, start with any one of the 8 dots.
draw or trace a horiz. line thru it towards the y-axis.

What number on the y axis does your horiz. line intersect?

Answer 10

Yeah, suppose you got B values as follows: 1, 2, 5, 6, 7, 7, 8. I count 7 such values.

Add up 1, 2, 5, 6, 7, 7, 8. I get 36. Div. 36 by 7 to get the average / mean.

Answer 11

36/7 will giv e you a mixed number that includes a decimal.

Answer 12

that was just an example.

Again, look at the given graph. There are 8 dots. Make a list of B-values, which are the y-values of these 8 dots.

Answer 13

Ah ok, so would the numbers be 1 2 2 3 3 5 6 8? @mathmale

Answer 14

Added together would be 30, and then divided by 8 would be 3.75.

Answer 15

Yes, that appears correct.
Add these 8 numbers together and div. the result by 8.

Answer 16

Yes, that's the "mean" that you wanted. (The mean of Variable B)

Answer 17

Is that the final answer though? Cause it says "Express answer to one decimal place."
What does that mean? @mathmale

Answer 18

Do I make it 3.8 by rounding up?

Answer 19

Only if you've been asked to do that. If you are, then 3.8 is correct. If you aren't, leave your answer as 3.75.

Answer 20

Ok thanks for your help!