Answer:
he probability that the sample mean deviates from the population mean = 112 by no more than 4= 0.9050
Step-by-step explanation:
mean = 112
sd = 12/sqrt(25) = 2.4
z = (x - μ)/σ
z = (116 - 112)/2.4 = 1.67
Therefore,
P(X >= 116) = P(z <= (116 - 112)/2.4)
= P(z >= 1.67)
= 1 - 0.9525
= 0.0475
z = (x - μ)/σ
z1 = (108 - 112)/2.4 = -1.67
z2 = (116 - 112)/2.4 = 1.67
Therefore, we get
P(108 <= X <= 116) = P((116 - 112)/2.4) <= z <= (116 - 112)/2.4)
= P(-1.67 <= z <= 1.67) = P(z <= 1.67) - P(z <= -1.67)
= 0.9525 - 0.0475
= 0.9050
Answer:
27/20
Step-by-step explanation:

The Answer to the question is B
Answer:
approximately 27 grams
Work Shown:
Half life formula
y = A*(0.5)^(x/H)
where,
A = starting amount = 30 grams
H = half life period = 90 years
x = number of years that pass by = 12
y = amount left over after x years
Let's plug the values for x, A and H into the formula to find y
y = A*(0.5)^(x/H)
y = 30*(0.5)^(12/90)
y = 27.3516746567466
y = 27 .... rounding to the nearest whole number