In a large population, 69% of the people have been vaccinated. If 4 people are randomly selected, what is the probability that At least one of them has been vaccinated?

0.991

Step-by-step explanation:

Let Q be probability none of the 4 are vaccinated.

Let P be probability that at least 1 is vaccinated.

P = 1 - Q

Now if 69% are vaccinated, then 31% are not vaccinated.

Thus any given person has a probability of 0.31 of not being vaccinated.

Q = (0.31)^4 = 0.00924

P = 1 - 0.00924 = 0.991

x + y = 90 5x – 10y = 90 90 – 10y = 5x 90 + 10y = 5x

step-by-step explanation:

last month maria hiked the 5-mile mountain trail a number of times and she hiked the 10-mile canal trail several times. let x represent the number of times she hiked the 5-mile trail, and let y represent the number of times she hiked the 10-mile trail. if she hiked a total of 90 miles, which equation can be used to find the number of times maria hiked each trail? x + y = 90 5x – 10y = 90 90 – 10y = 5x 90 + 10y = 5x

the solution is the point

step-by-step explanation:

we have

> equation a

> equation b

adds equation a and equation b

substitute the value of x in equation b to find the value of y

the solution is the point