X is your number
double it means 2 times x or 2x
add 4
2x+4
subtract my number
2x+4-x=x+4
subtract 3
x+4-3=x+1
the result is x+1 or your number plus 1
Answer:
Square
Step-by-step explanation:
From what it looks like I think it is a square
Answer:
The population standard deviation is not known.
90% Confidence interval by T₁₀-distribution: (38.3, 53.7).
Step-by-step explanation:
The "standard deviation" of $14 comes from a survey. In other words, the true population standard deviation is not known, and the $14 here is an estimate. Thus, find the confidence interval with the Student t-distribution. The sample size is 11. The degree of freedom is thus
.
Start by finding 1/2 the width of this confidence interval. The confidence level of this interval is 90%. In other words, the area under the bell curve within this interval is 0.90. However, this curve is symmetric. As a result,
- The area to the left of the lower end of the interval shall be
. - The area to the left of the upper end of the interval shall be
.
Look up the t-score of the upper end on an inverse t-table. Focus on the entry with
- a degree of freedom of 10, and
- a cumulative probability of 0.95.
.
This value can also be found with technology.
The formula for 1/2 the width of a confidence interval where standard deviation is unknown (only an estimate) is:
,
where
is the t-score at the upper end of the interval,
is the unbiased estimate for the standard deviation, and
is the sample size.
For this confidence interval:
Hence the width of the 90% confidence interval is
.
The confidence interval is centered at the unbiased estimate of the population mean. The 90% confidence interval will be approximately:
.
First you had to rewrite the problem with eighteen as the three times six is equal to eighteen.

Then you factor it out by the common term of six.

Final answer: 
Hope this helps!
And thank you for posting your question at here on brainly, and have a great day.
-Charlie
Answer:
fifth term
Step-by-step explanation:
The n th term of an AP is
= a₁ + (n - 1)d
where a₁ is the first term and d the common difference
Given a₃ = 4 and a₉ = - 8 , then
a₁ + 2d = 4 → (1)
a₁ + 8d = - 8 → (2)
Subtract (1) from (2)
6d = - 12 ( divide both sides by 6 )
d = - 2
Substitute d = - 2 into (1)
a₁ + 2(- 2) = 4
a₁ - 4 = 4 ( add 4 to both sides )
a₁ = 8
Thus equating the n th term formula to zero and solving for n
8 - 2(n - 1) = 0 ( subtract 8 from both sides )
- 2(n - 1) = - 8 ( divide both sides by - 2
n - 1 = 4 ( add 1 to both sides )
n = 5
The fifth term is equal to zero