Look at the link below I filled in the answers for you. :)
Answer:
50 boys
Step-by-step explanation:
2/4 = 1/2
25*2=50
Answer: -1
The negative value indicates a loss
============================================================
Explanation:
Define the three events
A = rolling a 7
B = rolling an 11
C = roll any other total (don't roll 7, don't roll 11)
There are 6 ways to roll a 7. They are
1+6 = 7
2+5 = 7
3+4 = 7
4+3 = 7
5+2 = 7
6+1 = 7
Use this to compute the probability of rolling a 7
P(A) = (number of ways to roll 7)/(number total rolls) = 6/36 = 1/6
Note: the 36 comes from 6*6 = 36 since there are 6 sides per die
There are only 2 ways to roll an 11. Those 2 ways are:
5+6 = 11
6+5 = 11
The probability for event B is P(B) = 2/36 = 1/18
Since there are 6 ways to roll a "7" and 2 ways to roll "11", there are 6+2 = 8 ways to roll either event.
This leaves 36-8 = 28 ways to roll anything else
P(C) = 28/36 = 7/9
-----------------------------
In summary so far,
P(A) = 1/6
P(B) = 1/18
P(C) = 7/9
The winnings for each event, let's call it W(X), represents the prize amounts.
Any losses are negative values
W(A) = amount of winnings if event A happens
W(B) = amount of winnings if event B happens
W(C) = amount of winnings if event C happens
W(A) = 18
W(B) = 54
W(C) = -9
Multiply the probability P(X) values with the corresponding W(X) values
P(A)*W(A) = (1/6)*(18) = 3
P(B)*W(B) = (1/18)*(54) = 3
P(C)*W(C) = (7/9)*(-9) = -7
Add up those results
3+3+(-7) = -1
The expected value for this game is -1.
The player is expected to lose on average 1 dollar per game played.
Note: because the expected value is not 0, this is not a fair game.
Answer:
The result will be inaccurate.
Step-by-step explanation:
A landscaper wants to find the answer to the question “How much time do people in Raleigh, North Carolina, spend doing yard work in one week?”
He asks the owners of all 120 houses in a Raleigh neighborhood.
The results of such a survey can never be accurate.
Firstly, the sample is not random as the person selected all the 120 houses in the neighborhood.
Secondly, few samples do not represent a large population. The city must have many lawns and the lawns of a single area does not denote the lawns of the entire city.
So, the results will be inaccurate.
