The time taken for the ball to fall a distance of 10feet is 1.25secs
Given the function modeled by the height expressed as:
f(t) =-16t² + 35
In order to determine the time taken by the all to fall a distance of 10 feet, hence;
f(t) = 10
10 = -16t² + 35
-16t² = 10 - 35
-16t² = -25
-t² = -25/16
t² = 25/16
t = √25/16
t = 5/4
t = 1.25secs
Hence the time taken for the ball to fall a distance of 10feet is 1.25secs
Learn more here: brainly.com/question/13881652
Answer:
one gadget costs $15.80
Step-by-step explanation:
Let w = cost of one widget
Let g = cost of one gadget
Given:
- Five widgets and three gadgets cost $109. 90
⇒ 5w + 3g = 109.9
Given:
- One widget and four gadgets cost $75. 70
⇒ w + 4g = 75.7
Rewrite w + 4g = 75.7 to make w the subject:
⇒ w = 75.7 - 4g
Substitute into 5w + 3g = 109.9 and solve for g:
⇒ 5(75.7 - 4g) + 3g = 109.9
⇒ 378.5 - 20g + 3g = 109.9
⇒ 378.5 - 109.9 = 20g - 3g
⇒ 268.6 = 17g
⇒ g = 15.8
Therefore, one gadget costs $15.80
To find the cost of one widget, substitute the found value for g into
w = 75.7 - 4g and solve for w:
⇒ w = 75.7 - 4(15.8)
⇒ w = 75.7 - 63.2
⇒ w = 12.5
Therefore, one widget costs $12.50
Answer:
The critical value is T = 1.895.
The 90% confidence interval for the mean repair cost for the washers is between $48.159 and $72.761
Step-by-step explanation:
We have the standard deviation for the sample, so we use the t-distribution.
The first step to solve this problem is finding how many degrees of freedom, we have. This is the sample size subtracted by 1. So
df = 8 - 1 = 6
90% confidence interval
Now, we have to find a value of T, which is found looking at the t table, with 6 degrees of freedom(y-axis) and a confidence level of 
. So we have T = 1.895, which is the critical value.
The margin of error is:
In which s is the standard deviation of the sample and n is the size of the sample.
The lower end of the interval is the sample mean subtracted by M. So it is 60.46 - 12.301 = $48.159
The upper end of the interval is the sample mean added to M. So it is 60.46 + 12.301 = $72.761
The 90% confidence interval for the mean repair cost for the washers is between $48.159 and $72.761
