Answer:
Step-by-step explanation:
Given that a fair coin is flipped twelve times.
It means the number of possible sequences of heads and tails would be:
2¹² = 4096
We can determine the number of ways that such a sequence could contain exactly 9 tails is the number of ways of choosing 9 out of 12, using the formula

Plug in n = 12 and r = 9


∵ 
∵ 

Thus, the probability will be:



Thus, the probability of the coin landing tails up exactly nine times will be:
Step-by-step explanation:
Let there be x blue ribbons

Answer:
5
Step-by-step explanation:
in each sample there were 50 students, in a group of 800 there would be 16 samples taken, if you divide the total amount of kids with Novemeber birthdays, 80 by the amount of samples, 16, youll learn that in each sample there are 5 students to have a birthday in november within each sample, hope this helps.
The amount of money Ben had to begin with after spending 1/6 and 1/2 of it is 57 dollars.
<h3>How to find the how much money he had with an equation?</h3>
let
x = amount he had to begin with
He spent 1/6 of his money on a burger, fries, and a drink. Therefore,
amount spent on burger, fries, and a drink = 1 / 6 x
Hence,
amount he had left = x - 1 / 6 x =6x - x /6 = 5 / 6 x
Then he spent half of the money he had left.
1 / 2(5 /6 x) = 5 + 8.25 + 10.50
5 / 12 x = 23.75
cross multiply
5x = 23.75 × 12
5x = 285
divide both sides by 5
x = 285 / 5
x = 57
Therefore, the amount of money he have to begin with is $57.
learn more on equation here: brainly.com/question/5718696
(x+3 ; y-5)
If you have (-2 ; 3) that means x = -2 and y = 3 so:
(-2+3 ; 3-5) = (1 ; -2)