Step-by-step explanation:
a. The point estimate is the mean, 47 days.
b. The margin of error is the critical value times the standard error.
At 31 degrees of freedom and 98% confidence, t = 2.453.
The margin of error is therefore:
MoE = 2.453 × 10.2 / √32
MoE = 4.42
c. The confidence interval is:
CI = 47 ± 4.42
CI = (42.58, 51.42)
d. We can conclude with 98% confidence that the true mean is between 42.58 days and 51.42 days.
e. We can reduce the margin of error by either increasing the sample size, or using a lower confidence level.
Answer:
32 5/8 (or 32 and 5/8)
Step-by-step explanation:
Okay, so this problem is asking for us to solve this problem with the substitution of a variable: x = -4. Before we fully solve this problem, we need to replace all of those x variables with -4 so that it is easier to solve.
-7 1/4(-4) + 3 5/8.
To make this problem even easier to solve, let's turn these mixed numbers into improper fractions. To do this, multiply the denominator by the whole number. Then add the numerator to this number. The new number that you just got is now your new numerator for this number.
-29/4(-4) + 3 5/8.
Repeat the last step to turn the other mixed number into an improper fraction.
-29/4(-4) + 29/8.
Now let's multiply that -4 by 29/4. Because a whole number technically has a denominator of 1, we can now set up the next part of our problem. (The symbol * means multiplication since we can't use x since it is already being used as a variable in this equation.)
(-29/4 * -4/1) + 29/8.
29 + 29/8.
Now to solve the rest of this problem, let's convert the whole number of 29 so that it has a denominator of 8. This is that these two numbers are addable.
<u>29</u> x <u>8</u> = <u>232</u>
1 x 8 = 8
Now these numbers are addable. So:
232/8 + 29/8 = 261/8 = 32 5/8.
I hope that this helps.
Answer:
3 hours
Step-by-step explanation:
To find the number of hours the plumber was at the house, we need to solve for x.
22x + 50 = 116
22x = 116 - 50
22x = 66
22x/22 = 66/22
x = 3
Answer:
All real numbers greater than or equal to -3
Step-by-step explanation:
we know that
The curved line could be a vertical parabola opening upwards with vertex at (2,-3)
The vertex is a minimum
The y-intercept is the point (0,1)
The x-intercepts are the points (0.25,0) and (3.75,0)
so
The domain is the interval -----> (-∞,∞)
All real numbers
The range is the interval ----> [-3,∞)
All real numbers greater than or equal to -3