Answer:
The expected revenue of the tour operator is 985.
Step-by-step explanation:
There are two outcomes:
Either less than 21 tourists show up and the operator does not have to pay anything. Or 21 tourists show up and the operator has to repay 100.
Anyways, initially he gets the price of all the tickets sold. That is 21 each at 50, so
.
Then, we need to find the probability that all of the 21 tourists show up. In this case, we have to subtract 100 from the revenue.
Each tourist has a 0.02 probability of not showing up. This means that each has a 1-0.02 = 0.98 probability of showing up. So the probability P that all 21 tourists show up is
.
So, the expected revenue of the tour operator is

Rounded up, the expected revenue of the tour operator is 985.
I think the correct answer is D
Answer:
210
Step-by-step explanation:
Formula I made up: (Don't copy it please) (x-1 + x-2 + x-3... until x-(x-1)
Add all answers possible. (4 true and falses with 2 different answers each.) (3 multiple choice with 4 possible outcomes.)
4 x 2 = 8 | 3 x 4 = 12 |
\ /
8 + 12 = 20
Do what I like to call Additional factorial. (it's a little different, so follow the formula above.)
x = 20
20 -1 + 20 - 2... 20-(20-1) = 210
19 + 18... + 1 = 210
Compare my answer to others if you get any because I am just in 8th grade and I am a nerd at math and I love it. Because I am in 8th grade, I have a slight possibility for being wrong. Enjoy the answer and thanks for letting me use my skills for the world. :)
Open circle with arrow going to the left
Answer:
The sum of three integers is 280.
a + b + c = 280
;
The sum of the first and second integers exceeds the third by 70.
a + b = c + 70
:
the third integer is 21 less than the first.
c = a - 21
:
Rearrange the 2nd equation and use elimination with the 1st equation
a + b + c = 280
a + b - c = 70
------------------subtraction eliminates a & b, find c
0 + 0 + 2c = 210
c = 210/2
c = 105
then
105 = a - 21
a = 105 + 21
a = 126
Find b using the 1st equation
126 + b + 105 = 280
b = 280 - 231
b = 49
:
:
See if that checks out
126 + 49 + 105 = 280
:
the three integers. 126, 49, 105