Answer:
x = 13
General Formulas and Concepts:
<u>Pre-Algebra</u>
Order of Operations: BPEMDAS
- Brackets
- Parenthesis
- Exponents
- Multiplication
- Division
- Addition
- Subtraction
Equality Properties
- Multiplication Property of Equality
- Division Property of Equality
- Addition Property of Equality
- Subtract Property of Equality<u>
</u>
<u>Algebra I</u>
<u>Trigonometry</u>
[Right Triangles Only] Pythagorean Theorem: a² + b² = c²
- a is a leg
- b is another leg
- c is the hypotenuse<u>
</u>
Step-by-step explanation:
<u>Step 1: Identify</u>
<em>a</em> = 12
<em>b</em> = 5
<em>c</em> = x
<u>Step 2: Solve for </u><em><u>x</u></em>
- Substitute in variables [PT]: 12² + 5² = x²
- Evaluate exponents: 144 + 25 = x²
- Add: 169 = x²
- [Equality] Square root both sides: ±13 = x
- Rewrite: x = ±13
Since we are dealing with positive numbers, we can disregard the negative root.
∴ x = 13
Standard deviation is calculated by
1. calculate mean, m
2. calculate deviation of EACH entry of data set from the mean, i.e.
d=(x-m)
3. calculate mean of square of deviations (d^2)/n to get variance,v
4. take square-root of variance to get standard deviation.
For example,
To find the standard deviation of data set {3,7,8}
1. mean=(3+7+8)/3=6
2. deviations, di={3-6,7-6,8-6}={-3,1,2}
3. squares of deviations, di^2={9,1,4}
4. mean of squares of deviations=(9+1+4)/3=14/3
Standard deviation=sqrt(14/3)=2.16
For the given data set, if you follow the above steps, you would get
sum=400
mean=400/9
variance (mean square of deviations)=8246/81
standard deviation=sqrt(8246/81)=sqrt(8246)/9
Answer:
Step-by-step explanation:
<u>∠2 and 121° are supplementary as consecutive interior angles:</u>
- m∠2 + 121° = 180°
- m∠2 = 180° - 121°
- m∠2 = 59°
Answer:
324
Step-by-step explanation:
given that in a poll, 74% of the people polled answered yes to the question "Are you in favor of the death penalty for a person convicted of murder?"
i.e. Sample proportion 
Margin of error = 4% = 0.04
Confidence level =90%
Z critical value for 90% = 1.645
Margin of error = 1.645 * std error
Hence std error = 
Std error is also equal to
Sample size should be 324.
The formula is sample size = (Z critical value)^2 (pq)/(Margin of error )^2
