Answer:
CI = (70.861 , 94.418)
Step-by-step explanation:
In order to determine the 90% confidence interval you use the following formula (for a population approximately normal):
(1)
: mean = 82.64
σ: standard deviation = 14.32
n: sample = 4
α: tail area = 1 - 0.9 = 0.1
Z_α/2 = Z_0.05: Z factor = 1.645
You replace these values and you obtain:

The confidence interval will be:

The 90% confidence interval is (70.861 , 94.418)
Answer:
It cooled 58.4 degrees
Step-by-step explanation:
T(t) = 68 + 144e ^(-.052t)
We want to find the value when t= 10
T(10) = 68 + 144e ^(-.052*10)
= 68 +85.611
T(10) =153.611
We also need to know
T(0)= 68 + 144e ^(-.052*0)
=68+144
=212
We want to know how much it cools
That would be the temperature at time 0 minus the temperature at time 10
T(0) - T (10)
212-153.611
58.389
To the nearest tenth
58.4 degrees
Answer:
3.3 or 10/3
Step-by-step explanation:
Answer:
Part A is 34
Part B is 2
Step-by-step explanation:
This question did provide some clues to answer this question. Every week, the area covered by the algae is multiplied by 2^1.
To find the area cover increase by the algae per day, the exponent should be divided by 7 since there are 7 days in a week. Hence, every day, the area covered by the algae multiplies by 2^(1/7). In other words, 1 day after the algae was spotted, the area is 12.5 * 2^(1/7), which answers part B.
10 days after the algae was spotted, the area covered by the algae is 12.5 * 2^[(1/7)*10] = 33.6475... , which rounds up to 34 and answers part A.
Step one:
ALWAYS set equation equal to zero, which in this case has already been done for us.
Step two:
Figure out what formula you need to use in order to solve in this case I'd use the Quadratic formula.
a=1
b=9
c=2
Quadratic formula:

Then you would plug in the information.

The solve for what is underneath the square root ONLY.

Since you cannot solve this any further, your final two answers are...
