Question

A.)Determine the probability that the sale chosen at random is a house for sale between 3 and 4 years old....
B.) What are the odds that the house is less then 9 years old

AGE: # Houses Sold:
1-2 1280
3-4 1580
5-6 1650
7-8 1510
9-10 1500

Answer 1

okay, lets do this together. what is the total number of houses?

Answer 2

7520

Answer 3

okay, what is the number of houses between 3 and 4 years old?

Answer 4

1580

Answer 5

okay. so what is the probability that any one of the 1580 houses will be chosen, given that there are 7520 total houses?

Answer 6

5940?

Answer 7

i have no idea

Answer 8

do you know anything about probability and sample sets?

Answer 9

not yet

Answer 10

then why are you doing this problem if you don't know probability?

Answer 11

because i need to learn how

Answer 12

okay. then I will explain probability to you.
suppose you have a dice. you roll it. what are the chances that it will land on the number 4?

Answer 13

1/6

Answer 14

yes. so there are one in 6 chances that the dice will roll 4.
what are the chances that the dice will roll an even number?

Answer 15

1/2

Answer 16

right. so what were are calling chances, are formally called probability.
probability of outcome that you want = set of the outcomes you want/set of all outcomes

Answer 17

so set of outcomes you want for the dice to roll even number is {2,4,6}. set of all outcomes is {1,2,3,4,5,6}.

Answer 18

ok i understand...so in relation to that problem

Answer 19

so what is the set of outcomes you want?

Answer 20

in my problem?

Answer 21

I dont know what that means

Answer 22

okay in the dice problem, the set of outcomes you wanted was of size 3. the set of all outcomes was of size 6. so the probability of even number was 3/6 or 1/2 correct?

Answer 23

correct

Answer 24

so what is the desired outcome in your problem?

Answer 25

I dont know how to figure that out

Answer 26

its given in the problem. the desired outcome is you choose a house 3-4 years old. so how many houses are 3-4 years old?

Answer 27

1580

Answer 28

and what is the set of all outcomes?

Answer 29

7520?

Answer 30

right. you have to choose one house and its set is all the houses in that area. So the set size is 7520.
so what is the probability that you choose one of the 1580 houses?

Answer 31

7520/1580...then simplify?

Answer 32

no no. probability is the set of desired/ total. you have done total/desired.

Answer 33

probability cannot be greater than 1.

Answer 34

soo 1580/7520 then simplify

Answer 35

right.

Answer 36

okay so .21

Answer 37

im sure you did the calculation right.

Answer 38

now, for the other part. what are the odds that you choose a house less than 9 years old?

Answer 39

what is the desired outcome?

Answer 40

6020

Answer 41

i know that it is some number to 75

Answer 42

okay so desired outcome/total outcome = ?

Answer 43

6020/7520

Answer 44

.80

Answer 45

ok. you have your answers.

Answer 46

so the answer is what to 75?

Answer 47

what to 75? what does that mean?

Answer 48

because in my problem it says what are the odds the house is less then 9 years old....it has a fill in the blank of ? number to 75

Answer 49

oh okay. then the number you are looking for is 0.8 times 75

Answer 50

60

Answer 51

your probability is 0.8. it can be expressed as 4/5 or 80/100 or 60/75 in your case.