Answer:
The value is 
Step-by-step explanation:
From the question we are told that
The mean is 
The standard deviation is 
The safest water level is between 7.2 and 7.8
Generally the probability that the selected pool has a pH level that is not considered safe is mathematically represented as
Here
Generally 
So
=> 
From the z-table the probability of (Z < -1.5) and ( Z <1.5) are
and
So
So
=>
(a) 0.059582148 probability of exactly 3 defective out of 20
(b) 0.98598125 probability that at least 5 need to be tested to find 2 defective.
(a) For exactly 3 defective computers, we need to find the calculate the probability of 3 defective computers with 17 good computers, and then multiply by the number of ways we could arrange those computers. So
0.05^3 * (1 - 0.05)^(20-3) * 20! / (3!(20-3)!)
= 0.05^3 * 0.95^17 * 20! / (3!17!)
= 0.05^3 * 0.95^17 * 20*19*18*17! / (3!17!)
= 0.05^3 * 0.95^17 * 20*19*18 / (1*2*3)
= 0.05^3 * 0.95^17 * 20*19*(2*3*3) / (2*3)
= 0.05^3 * 0.95^17 * 20*19*3
= 0.000125* 0.418120335 * 1140
= 0.059582148
(b) For this problem, let's recast the problem into "What's the probability of having only 0 or 1 defective computers out of 4?" After all, if at most 1 defective computers have been found, then a fifth computer would need to be tested in order to attempt to find another defective computer. So the probability of getting 0 defective computers out of 4 is (1-0.05)^4 = 0.95^4 = 0.81450625.
The probability of getting exactly 1 defective computer out of 4 is 0.05*(1-0.05)^3*4!/(1!(4-1)!)
= 0.05*0.95^3*24/(1!3!)
= 0.05*0.857375*24/6
= 0.171475
So the probability of getting only 0 or 1 defective computers out of the 1st 4 is 0.81450625 + 0.171475 = 0.98598125 which is also the probability that at least 5 computers need to be tested.
Answer:
Greatest number of flowers that can be used in a bouquet is 8.
Step-by-step explanation:
In this question greatest number of flowers used in a bouquet will be decided by the "Greatest Common Factor" of the numbers of the flowers given.
So, factors of 16 = 1×2×2×2×2
Factors of 8 = 1×2×2×2
Factors of 32 = 1×2×2×2×2×2
Common factors = 1×2×2×2
Greatest Common Factor of these numbers will be = 1×2×2×2 = 8.
Therefore, greatest number of flowers that could be in a bouquet is 8.
If a square-shaped pool with side lengths are 3a^5 then find
the area of the pool
solution:
A = (3a^5) x (3a^5)
= 9a^5+5
= 9a^10
The area of the square-shaped pool are 9a^10 based on the given side length which is 3a^5
The question is Max owes Becky for the movie how much.. the pizza information is a distractor.
Max has a coupon for 1/2 off a third movie ticket when 2 are purchased for regular price of $9.80
2 x (9.80) + 1/2 x (9.80) = 19.60 + 4.90 = $24.50 total all 3 tickets
Since they agree to split the cost equally, divide total cost by 3
24.50 / 3 = $8.16 each
The answer is: Between $8 and $10
