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:
Step-by-step explanation:
Answer:
a) Shawn's error was that he Multiplied 15 by 2x only. He didn't Multiply 15 by 7
b) The difference, in square feet, between the actual area of Shawn’s garden and the area found using his expression is given as
98 square feet
Step-by-step explanation:
The area in, square feet, of Shawn’s garden is found be calculating 15(2x + 7). Shawn incorrectly says the area can also be found using the expression 30x + 7.
The correct area =
15(2x + 7).
= 30x + 105 square feet
The error in Shawn’s expression is
= 15(2x + 7)
= 30x + 7 square feet
Shawn's error was that he Multiplied 15 by 2x only. He didn't Multiply 15 by 7
The difference, in square feet, between the actual area of Shawn’s garden and the area found using his expression is given as
30x + 105 square feet - 30x + 7 square feet
= 30x + 105 - (30x + 7)
= 30x - 30x + 105 - 7
= 98 square feet
Sorry do know that one !!☹️
