Question

The following graphs have a scale assigned to them: the area of each grid square is 0.1 square units. Which ones are density curves ? Check all that apply.

http://assets.openstudy.com/updates/attachments/4e447ac00b8b3609c71ff2e6-clint.m-1313110735120-screenshot20110811at7.53.32pm.png

Answer 1

A density curve shows you the distribution of the data. This gives us two basic requirements
1st, data can only be 0 or positive. Think about, for example, looking at the distribution of the heights of your classmates. You could have a lot of classmates around 5'8'', you could have just a few classmates around 6'0'', you could have no classmates around 4'0''. But you could never have fewer than 0 classmates at any particular height. So that means our distribution should always be positive, that is, above the x axis.

Answer 2

2nd requirement: The amount under the line for any point tells you what amount of the data occurs at that point. If you add up all of those things, you should have ALL of the data, which is 1. So the area under your curve should add up to 1.

Answer 3

C it kinda dips under,. a negative.. so that wouldnt work?

Answer 4

Right. C is a no go because it's under the curve.
Check the other ones to see if their area adds up to 1.

Answer 5

You're told that the area of each box is .1
How many boxes should there be to add up to 1?

Answer 6

10- A and D have 10 not sure about E?

Answer 7

E is a little bit tricky. Do you know how to calculate the area of a triangle?

Answer 8

negative.

Answer 9

So B is a no go?

Answer 10

B is a no go. =)
Usin' my lingo... lols

Answer 11

Sound like you are in the military lol..

Answer 12

Okay, I started to explain to you how to calculate that as a triangle, but it turns out to be pretty complicated.
Instead, just count up whole squares. Then try to put together parts of squares to make squares.

Answer 13

Haha not in the miliatary, no.

Answer 14

Well the first time i chose answers i only chose A and D so i guessing that if B and C are a no go.. then i choose A,D,& E :)

Answer 15

Right =)
E is a little tricky to see, but you can put together parts of squares to make whole squares.

Answer 16

And it has area of 10.

Answer 17

Not 10, but 1. 10 squares.

Answer 18

yea I understand,.. great! :) LOL maybe now I will pass this and move on.

Answer 19

Haha good =) Glad I could help you understand.