Answer:
Boulder's maximum height is 226 ft.
It take 3.5 seconds the Boulder to reach its maximum height.
Step-by-step explanation:
Given :
A catapult launches a boulder with an upward velocity of 112 ft/s.
The height of the Boulder, h, in feet
After t seconds is given by the function :
--(a)
A quadratic function can be graphed using a table of values. The graph creates a parabola.
If the coefficient of the squared term is positive then the parabola opens up and The vertex of this parabola is known as the minimum point.
If the coefficient of the squared term is negative then the parabola opens down and The vertex of this parabola is known as the maximum point.
Now we will use vertex formula to calculate t
When
then vertex will be
Now consider the given function:
where a = -16
b=112
so using vertex formula :
Thus, it take 3.5 seconds the Boulder to reach its maximum height.
Now to calculate the Boulder's maximum height . Put value of t = 3.5 in given function (a)
Thus, Boulder's maximum height is 226 ft.
Answer:
3648
Step-by-step explanation:
Answer:
n=97
Step-by-step explanation:
1) Notation and definitions
population standard deviation known
Confidence=90% or 0.9
n sample size required (variable of interest)
A confidence interval is "a range of values that’s likely to include a population value with a certain degree of confidence. It is often expressed a % whereby a population means lies between an upper and lower interval".
The margin of error is the range of values below and above the sample statistic in a confidence interval.
Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".
The sample mean have the following distribution
2) Calculation for the sample size required
In order to find the critical value we need to take in count that we are finding the interval for the mean with the population deviation known, so on this case we need to use the z distribution. Since our interval is at 90% of confidence, our significance level would be given by and . And the critical value would be given by:
The margin of error for the sample mean interval is given by this formula:
(a)
And on this case we have that and we are interested in order to find the value of n, if we solve n from equation (a) we got:
(b)
And replacing into equation (b) the values from part a we got:
And rounded up we have that n=97
B. The age of my friend.
C. The number of kittens in a litter.
D. There are 24 hours in a day.