Answer:
Exact form: -7/10
Decimal form: -0.7
Step-by-step explanation:
Isolate the variable by dividing each side by by factors that don't contain the variable.
Answer:
d. 20
Step-by-step explanation:
Standard deviation is 4.5
Margin error for the problem is 2 hours
Probability 95%, that means that the siginficance level α is 1 – p
α = 1 – 0.95 = 0.05
margin of error (ME) can be defined as follows
ME = Z(α/2) * standard deviation/ √n
Where n is the sample size
Z(0.05/2) = Z(0.025)
Using a z table Z = 1.96
Now, replacing in the equation and find n
2 = 1.96 * 4.5/ √n
2 = 8.82/√n
√n = 8.82/2
√n = 4.41
n = 4.41^2
n = 19.44 ≈ 20
Answer: 195
Step-by-step explanation:
Cost per student = $4
Total number who attended = n
The cost of the total of student who attended will be cost per student multiplied by the total number of students, that is
Total cos = 4n
Since, they are to pay $140 , for publicity, then the total cost becomes
T = 4n - 140
From the last statement
4n - 140 ≥ 640
4n ≥ 640 + 140
4n ≥780
n ≥ 780/4
n ≥ 195
That means at least 195 students must attend if the science club is to earn at least $ 640
Answer:
Step-by-step explanation:
Area of a circle = pi x square of radius = 30.190 ft
Answer:
4 hours
Step-by-step explanation:
3+1=4
