Answer:
The student made an error during the distributive property in the second step where they multiplied 0.15 by -0.2 to equal -0.3 when it should have been -0.03.
Step-by-step explanation:

Answer:
A sample of 18 is required.
Step-by-step explanation:
We have that to find our
level, that is the subtraction of 1 by the confidence interval divided by 2. So:
Now, we have to find z in the Z-table as such z has a p-value of
.
That is z with a pvalue of
, so Z = 1.88.
Now, find the margin of error M as such
In which
is the standard deviation of the population and n is the size of the sample.
A previous study indicated that the standard deviation was 2.2 days.
This means that 
How large a sample must be selected if the company wants to be 92% confident that the true mean differs from the sample mean by no more than 1 day?
This is n for which M = 1. So



Rounding up:
A sample of 18 is required.
Answer:
3(a - b)(a + b)
Step-by-step explanation:
Factorize: (2a - b)² - (a - 2b)²
- Different of Perfect a Square rule: a² - b² = (a + b)(a - b)
(2a - b)² - (a - 2b)² = [(2a - b) + (a - 2b)] × [(2a - b) - (a - 2b)]
1. Distribute and Simplify:
Distribute the (+) sign on the first bracket and simplify: [(2a - b) + (a - 2b)] → 2a - b + a - 2b → (3a - 3b)
Distribute the (-) sign on the first bracket and simplify: [(2a - b) - (a - 2b)] → 2a - b – a + 2b → (a + b)
We now have:
(3a - 3b)(a + b)
2. Factor out the Greatest Common Factor (3) from 3a - 3b:
(3a - 3b) → 3(a - b)
3. Add "(a + b)" back into your factored expression:
3(a - b)(a + b)
Hope this helps!
Answer:
area = 6x^2+10x-4 perimeter= 5x+3
Step-by-step explanation:
If you would like to solve the equation k / 2 + 9 = 30, you can calculate this using the following steps:
k / 2 + 9 = 30
k / 2 = 30 - 9
k / 2 = 21 /*2
k = 21 * 2
k = 42
The result is 42.