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.
Answer:
x = - 1
Step-by-step explanation:
Given
- 4(3x - 7) = 40 ( divide both sides by - 4 )
3x - 7 = - 10 ( add 7 to both sides )
3x = - 3 ( divide both sides by 3 )
x = - 1
1- The answer is that she wants the new time to be 32 minutes
Solution: The question asks that she wants to DECREASE by 20%
What you will do it convert 20% to a decimal (which is 0.20)
Then, you need to multiply the minutes by the decimal:
40 x 0.20 = 8 minutes
Now you know that 8 minutes will be 20% of 40 minutes, so you just subtract 8 from 40 UwU
