Step-by-step explanation:
A study was to be undertaken to determine if a particular training program would improve physical fitness. A sample of 31 university students was selected to be enrolled in the fitness program. The researchers wished to determine if there was evidence that their sample of students differed from the general population of untrained subjects. The sample mean is 47.4 and a standard deviation of 5.3. The 98% confidence interval is determined and is given as, (45.2, 49.6) .
If the level of confidence is changed to 95%, then the confidence interval will become shorter but the p-value will not change because it is calculated using the test statistic. So the correct answer is (a).
Answer:
Jeff mows 9 yards of lawn in 30 minutes
Step-by-step explanation:
The equation that models the amount of time (t) in minutes it takes Jeff to mow an average sized yard is 
, where n is the number of yards he mows.
To find the number of yards Jeff mows in 30 minutes, we set the equation to 30 and solve for n.
Add -12 to both sides:
Divide both sides by 2
Hence Jeff mows 9 yards of lawn in 30 minutes.
<h3>
Answer: Max height = 455.6 feet</h3>
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Explanation:
The general equation
y = ax^2 + bx + c
has the vertex (h,k) such that
h = -b/(2a)
In this case, a = -16 and b = 147. This means,
h = -b/(2a)
h = -147/(2*(-16))
h = 4.59375
The x coordinate of the vertex is x = 4.59375
Plug this into the original equation to find the y coordinate of the vertex.
y = -16x^2+147x+118
y = -16(4.59375)^2+147(4.59375)+118
y = 455.640625
The vertex is located at (h,k) = (4.59375, 455.640625)
The max height of the rocket occurs at the vertex point. Therefore, the max height is y = 455.640625 feet which rounds to y = 455.6 feet
Answer:
Step-by-step explanation:
Solve the brackets first.
Division comes next.
Cancel the negative signs.
Multiply the terms.
20, 20, 20, 30, 20
Tip for rounding nearest 10th: if the 2nd number is above 5 it’s the one above, if it’s below 5 it’s the one below.
