Answer:
a) 0.8413
b) 421
c) 
Step-by-step explanation:
We are given the following information in the question:
Mean, μ = 165
Standard Deviation, σ = 15
We are given that the distribution of IQ examination scores is a bell shaped distribution that is a normal distribution.
Formula:
a) P(IQ scores at most 180)
P(x < 180)
Calculation the value from standard normal z table, we have,
b) Number of the members of the club have IQ scores at most 180
n = 500

c) P(X< x) = 0.95
We have to find the value of x such that the probability is 0.95
Calculation the value from standard normal z table, we have,


Answer:
57
Step-by-step explanation:
Let c represent the number of children ($1.75 each) and a represent the number of adults ( $2.00 each).
We know that there were 340 people total, so c + a = 340. This implies that a = 340 - c
We also know that $1.75 c + $2.00 a = $609.25
By substituting a with 340 -c we have $1.75 c + $2.00 (340 -c) = $609.25
Use the distributive property to obtain $1.75 c + $680 - $2.00 c = $609.25
Subtract $680 from both sides and combine like terms to get - $0.25 c = -
$70.75
Now, divide both sides by -$0.25 to get c = 283, the number of children.
The number of adults is 340 - c or 340 - 283 = 57
Answer: -16
Step-by-step explanation:
49 would be the result of -7 squared. Due to the fact it is negative, it would cancel out to be positive.
For the numerator, 49-1 is equivalent to 48.
48/x+4
-7+4 = -3
48/-3
= -16
Answer:
C = 39 pi meters
Step-by-step explanation:
The circumference of a circle is given by
C = 2 * pi * r
C = 2 * pi * 19.5
C = 39 pi meters
Answer:
Step-by-step explanation:
Using the formula
p +/- z* √(p(1-p) / n)
Where p is sample proportion = 3226/3957 = 0.8153, n = 3957 and z* is 2.576
0.8153 + (2.576 √(0.8153(1-0.8153) / 3957))
0.8153 + (2.576 √ (0.8153(0.1847) /3957)
0.8513 + (2.576 √(0.1572/3957)
0.8513 + (2.576 √0.00003974)
0.8513 + 2.576(0.0063)
0.8513 + 0.016
0.8670 ~ 87%
For the lower interview
0.8513 - 0.016
= 0.8353 ~ 84%
Thus, at 99% confidence interval is 84% and 87%