Answer:
(B) 0.057
Step-by-step explanation:
The 95% confidence interval is (0.028, 0.086). The formula for the confidence interval is μ ± e where μ is the mean and e is the margin of error.
Therefore the confidence interval is (μ - e , μ + e).
That is μ - e = 0.028 and μ + e = 0.086
To get the point estimate which is the mean, we sum the two proportions and divide it by two.
Therefore point estimate (μ) = (0.028 + 0.086) / 2 = 0.057
Let m and j be the current ages of Matthew and Jenny, respectively.
Now, Matthew is 3 times as old as Jenny, so the variables are in the following relation:

In 7 years, both of them will be 7 years older, i.e. their ages will be m+7 and j+7, and Matthew will be twice as old:

Now, remembering that m=3j, we can rewrite the second equation as

So, Jenny is 7 and Matthew is 21 (he's 3 times older).
In fact, in 7 years, they will be 14 and 28, and Matthew will be twice as old.
Answer:
y + 1 = -1/2(x - 8)
General Formulas and Concepts:
<u>Pre-Algebra</u>
Order of Operations: BPEMDAS
- Brackets
- Parenthesis
- Exponents
- Multiplication
- Division
- Addition
- Subtraction
<u>Algebra I</u>
Slope Formula: 
Point-Slope Form: y - y₁ = m(x - x₁)
- x₁ - x coordinate
- y₁ - y coordinate
- m - slope
Step-by-step explanation:
<u>Step 1: Define</u>
f(8) = -1 → Coordinate (8, -1)
f(6) = 0 → Coordinate (6, 0)
<u>Step 2: Find slope </u><em><u>m</u></em>
- Substitute [SF]:

- Add/Subtract:

- Simplify:

<u>Step 3: Write Function</u>
<em>Substitute into general form.</em>
- Point 1: y + 1 = -1/2(x - 8)
- Point 2: y = -1/2(x - 6)
Answer:
A
Step-by-step explanation:
Answer:
Selling price= $580
Step-by-step explanation:
eGiving the following information:
Buying price= $400
Mark-up percentage= 45% = 0.45
<u>The manager applies a mark-up equivalent to 45% of the buying price. First, we need to determine how much is 45% of the cost.</u>
Mark-up= buying price* Mark-up percentage
Mark-up= 400*0.45
Mark-up= $180
<u>Now, the selling price:</u>
Selling price= 400 + 180
Selling price= $580