Answer: We are 95% confident that the mean income for all residents of this city is between $26700 and $35400.
Step-by-step explanation:
We know that a 95% confidence interval given an interval of values that we can be 95% sure , that it contains the true mean of the population, not 95% of data lies in it.
Given : A researcher is estimating the mean income of residents in a large city. The income variable is usually skewed to the right. She collects a random sample of 25 people.
The resulting 95% confidence interval is ($26700, $35400).
Then, valid conclusion will be : We are 95% confident that the mean income for all residents of this city is between $26700 and $35400.
Answer:
Step-by-step explanation:
Check the picture
Together it would take 3 hours.
Team A can wrap all gifts in 7 hours; thus they can wrap 1/7 of the gifts in 1 hour.
Team B can wrap all gifts in 5 hours; thus they can wrap 1/5 of the gifts in 1 hour.
1/7h + 1/5h = 1, where h is the number of hours; it equals 1 because it is 100% of the gifts;
Find a common denominator. 35 is the first thing 7 and 5 will both divide into. Convert the fractions:
5/35h + 7/35h = 1
12/35h = 1
Divide both sides by 12/35:
12/35h ÷ 12/35 = 1 ÷ 12/35
h = 1/1 ÷ 12/35
h = 1/1 × 35/12
h = 35/12
h = 2.9
h ≈ 3
Which zero though? Please specify and then I’ll answer in the comments
Answer:
x=4
Step-by-step explanation:
In order to solve for x, we must isolate x on one side of the equation.
x+3x+5=21
First, combine like terms. x and 3x are both terms with variables, and can be combined.
(x+3x) + 5=21
4x + 5=21
5 is being added to 4x. The inverse of addition is subtraction. Subtract 5 from both sides of the equation.
4x+5-5= 21-5
4x= 16
x is being multiplied by 4. The inverse of multiplication is division. Divide both sides by 4.
4x/4=16/4
x= 16/4
x=4
Let's check our solution. Plug 4 in for x and solve.
x+3x+5=21
4+3(4)+5=21
4+12+5=21
16+5=21
21=21
This solution checks out, so we know our answer is correct.
x is equal to 4, x=4.
