Answer: c. 39.14 to 42.36
Step-by-step explanation:
We want to determine a 95% confidence interval for the average hourly wage (in $) of all information system managers
Number of sample, n = 75
Mean, u = $40.75
Standard deviation, s = $7.00
For a confidence level of 95%, the corresponding z value is 1.96. This is determined from the normal distribution table.
We will apply the formula
Confidence interval
= mean +/- z ×standard deviation/√n
It becomes
40.75 +/- 1.96 × 7/√75
= 40.75 ± 1.96 × 0.82
= 40.75 + 1.6072
The lower end of the confidence interval is 40.75 - 1.6072 =39.14
The upper end of the confidence interval is 40.75 + 1.6072 =42.36
1 in 4
4 suits, each with the same number of cards. 1/4 of the cards are diamonds, so theres a 1 in 4 chance of drawing one.
Where’s the rest of the question??
ANSWER
Yes, it is a quadratic equation which is x² + 3x - 70 = 0
SOLUTION
Area = Length × Width
Let x be the Length, L = x
Length is 3 cm longer than its width, thus, W = x + 3
The Area is equal to 70m², thus, A = 70m²
In Mathematical representation,
A = L × W
70 = (x)(x + 3)
70 = x(x) + x(3)
70 = x² + 3x
0 = x² + 3x - 70