Let X be a discrete binomial random variable.
Let p = 0.267 be the probability that a person does not cover his mouth when sneezing.
Let n = 18 be the number of independent tests.
Let x be the number of successes.
So, the probability that the 18 individuals, 8 do not cover their mouth after sneezing will be:
a) P (X = 8) = 18! / (8! * 10!) * ((0.267) ^ 8) * ((1-0.267) ^ (18-8)).
P (X = 8) = 0.0506.
b) The probability that between 18 individuals observed at random less than 6 does not cover their mouth is:
P (X = 5) + P (X = 4) + P (X = 3) + P (X = 2) + P (X = 1) + P (X = 0) = 0.6571.
c) If it was surprising, according to the previous calculation, the probability that less than 6 people out of 18 do not cover their mouths is 66%. Which means it's less likely that more than half of people will not cover their mouths when they sneeze.
I hope this helps you
4.1+4. (-x)+2x=3.x+3.1
4-4x+2x=3x+3
-2x-3x=3-4
-5x= -1
x=1/5
Write a system of equations and solve.
x + y = 10
5x + 10y = 90
Multiply and combine equations
-5x - 5y = -50
5x + 10y = 90
------------------
5y = 40
y = 8
x = 2
There are 2 nickels and 8 dimes in the jar. Hope this helps! :)
Answer:
3 out of 18
i think
Step-by-step explanation:
5cos (2x)+7=cos (2x)+8, 4cos (2x)=1, cos (2x)=1/4, 2x=arccos(1/4), x=(1/2)arccos (1/4). I used x instead of theta, and arccos is cos inverse
