Reading Pictographs

u08_l1_t1_we1 Reading Pictographs

According to the pictograph below, how many survey respondents

have type O positive blood ? How many have O negative blood ?

So pictograph is really just a way of representing data with pictures that are

somehow related to the data

So in this case they give us little pictures of am assuming blood drops

right over here

And they tell us

each blood drop

each blood drop in this pictograph represents 8 people

so you can kinda view that as the scale of these graphs

Each of this is 8 people

So, For Example

You say how many people have A positive would be

1, 2, 3, 4, 5 , 6 , 7 blood drops

but each of those blood drops represent 8 people, so it would be 56

people have type A positive

But, lets answer the actual question that they are asking us

How many survey respondents have type O positive

O Positive

So this is O and then we care about O positive

So we have, 1 blood drop, 2, 3

Let me just do this in a new different color.

We have 1, 2, 3, 4, 5, 6, 7, 8

So we have 8 drops

I'll put those in quotes cause of the pictures of drops

and then the scale is,the scale is 8 people. 8 people

Let me write it this way

Times 8 people per drop

8 people per drop

and so, 8 times and 8 and actually the drops you can view them as cancelling out

if you view them as units

so drops, drops

8 times 8 is equal to 64

64 people

So they could have literally written the number 64 right over here

64 People have type O positive blood

So now lets think about the O negative case

O negative blood

Well this is O and then within the blood group O

This is O negative

and we have 1 drop, 2 drops

So we have 2 drops

Two Drops

Times 8 people per drop

8 people per drop

so 2 times 8.

each of these represent 8

So 8 and then 16

Or, 2 times 8 is equal to 16, 16 people

so 16 of the survey respondents

16 have type O negative and 64 have type O positive