Step-by-step explanation:
B. Yes, we are 99% confident that the population mean is within the interval.
C. Yes, 225 is below the interval minimum, so it is reasonable to conclude the average cholesterol level is greater than 225 mg/dl.
D. No. Increasing the sample size would decrease the margin of error, so the ends of the interval would move closer to the sample mean of 251.9. So the interval minimum would still be higher than 225.
Answer:
B. (2a +3b)(4a -c)
Step-by-step explanation:
Group the terms pairwise, then factor each pair.
... (8a² -2ac) +(12ab -3bc)
2a is a common factor in the first pair of terms; 3b is a common factor in the second pair of terms. We can factor those out.
... = 2a(4a -c) +3b(4a -c)
Then we see that (4a-c) is a common factor in the result. We can factor that out.
... = (2a +3b)(4a -c) . . . . matches selection B
Answer:
Let's talk through this a one step at a time.
*Since f(x) is concave-up with its vertex on the x-axis, we know f(x) ≥ 0.
*We also know that when we shift a function's domain by a positive number, we shift the function left and when we shift a function's domain by a negative number, we shift the function right. So f(x-5) is f(x) shifted to the right by 5.
*At this point, f(x-5) has its vertex at (5,0).
*When we negate f(x-5), the parabola becomes concave down yet the vertex remains at (5,0). Now we're at -f(x-5). At this point we have -f(x-5)≤0 with a range (-∞,0]
*If we add 2 to create g(x)=2-f(x-5), then we have a concave down parabola with its vertex shifted up by 2, at (5,2). So, g(x) is concave down with its vertex at (5,2). Hence
The interest is $453.60.
The total amount includes principal + interest. The principal was 630 and the total amount was 1083.60.
1083.60 - 630 = 453.60.
