Answer:
the answer for this question is c
To calculate expected value,
We can add up the probability of all possible events.
The 2 possible events are either winning $50 or losing the prize, which is $ - 50
Expected value =
50 x 40 % + (-50) x 60%
= $-10
So the answer is $-10
Answer:
0.0014 = 0.14% probability that Ashley, Bob, Claire, and Daniel will be chosen.
Step-by-step explanation:
A probability is the number of desired outcomes divided by the number of total outcomes.
The order in which the students are chosen is not important, so the combinations formula is used to solve this question.
Combinations formula:
is the number of different combinations of x objects from a set of n elements, given by the following formula.
Desired outcomes:
4 students from a set of 4(Ashley, Bob, Claire, and Daniel). So
Total outcomes:
4 students from a set of 13(number of students in the lottery). So
Probability:
0.0014 = 0.14% probability that Ashley, Bob, Claire, and Daniel will be chosen.
This is a system of equations. You can solve it by substitution or elimination. I'm going to use substitution x - 2y = -4.5; add 2y to each side x - 2y + 2y = -4.5 + 2y; simplify x = 2y - 4.5 2(2y - 4.5) + 3y = 12 4y - 9 + 3y = 12 7y - 9 = 12 7y - 9 + 9 = 12 + 9 7y = 21 y = 3 <--------first answer x - 2y = -4.5 x - 2(3) = -4.5 x - 6 = -4.5 x -6 + 6 = -4.5 + 6 x = 1.5 <--------second answer Check: 2(1.5) + 3(3) = 12? 3 + 9 = 12? 12 = 12; It checks 1.5 - 2(3) = -4.5? 1.5 - 6 = -4.5? -4.5 = -4.5; It checks x = 1.5 and y = 3 <-----------Final Answer
Answer:
p=-36
Step-by-step explanation:
-18=p/2
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Multiply both sides by 2
-18(2)= p/2 (2)
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-36 = p
switch the sides of the equation
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p=-36