Add-one fourth to 5 times b

A seed is planted 2 inches below the ground.

jeka57 [31]

Six Subtract 2 Equals Four :)

7 0

2 years ago

A high school principal wishes to estimate how well his students are doing in math. Using 40 randomly chosen tests, he finds tha

ollegr [7]

Answer:

99% confidence interval for the population proportion of passing test scores is [0.5986 , 0.9414].

Step-by-step explanation:

We are given that a high school principal wishes to estimate how well his students are doing in math.

Using 40 randomly chosen tests, he finds that 77% of them received a passing grade.

Firstly, the pivotal quantity for 99% confidence interval for the population proportion is given by;

P.Q. = $\frac{\hat p-p}{\sqrt{\frac{\hat p(1-\hat p)}{n} } }$ ~ N(0,1)

where, $\hat p$ = sample proportion of students received a passing grade = 77%

n = sample of tests = 40

p = population proportion

Here for constructing 99% confidence interval we have used One-sample z proportion test statistics.

So, 99% confidence interval for the population proportion, p is ;

P(-2.5758 < N(0,1) < 2.5758) = 0.99 {As the critical value of z at 0.5%

level of significance are -2.5758 & 2.5758}

P(-2.5758 < $\frac{\hat p-p}{\sqrt{\frac{\hat p(1-\hat p)}{n} } }$ < 2.5758) = 0.99

P( $-2.5758 \times {\sqrt{\frac{\hat p(1-\hat p)}{n} } }$ < ${\hat p-p}$ < $2.5758 \times {\sqrt{\frac{\hat p(1-\hat p)}{n} } }$ ) = 0.99

P( $\hat p-2.5758 \times {\sqrt{\frac{\hat p(1-\hat p)}{n} } }$ < p < $\hat p+2.5758 \times {\sqrt{\frac{\hat p(1-\hat p)}{n} } }$ ) = 0.99

99% confidence interval for p = [ $\hat p-2.5758 \times {\sqrt{\frac{\hat p(1-\hat p)}{n} } }$ , $\hat p+2.5758 \times {\sqrt{\frac{\hat p(1-\hat p)}{n} } }$ ]

= [ $0.77-2.5758 \times {\sqrt{\frac{0.77(1-0.77)}{40} } }$ , $0.77+2.5758 \times {\sqrt{\frac{0.77(1-0.77)}{40} } }$ ]

= [0.5986 , 0.9414]

Therefore, 99% confidence interval for the population proportion of passing test scores is [0.5986 , 0.9414].

Lower bound of interval = 0.5986

Upper bound of interval = 0.9414

6 0

2 years ago

Graph the function y = 4 . Then use the graph to find the missing x- or y-coordinates for the function to the nearest hundredth.

Elodia [21]

Given equation is y=4.

Question says to graph the given equation y=4 then use the graph to find the missing x- or y-coordinates for the function to the nearest hundredth.

Equation y=4 has no "x" so that means line y=4 will be a horizontal line which passes through 4 on y-axis.

Since it is parallel to x-axis so that means there is no x-intercept.

y-intercept is (0,4) as the line crosses at 4 on y-axis.

5 0

2 years ago

The ratio of boys to girls at King Middle school is 3:2. What is the ratio of girls to all students?

Dominik [7]

The answer is: " 2 :5 " ; or, write as: " 2/5 " .
________________________________________________________
The ratio of 'girls' to 'all students' is: "2: 5 " ; or, write as: " 2/5 ".
________________________________________________________
Explanation:
________________________________________________________
Given: The ratio of boys to girls is: " 3:2 " .

Problem: Find the ratio of "girls" to "all students:
________________________________________________________
Note: This ratio of "boys to girls", which is " 3 : 2 " ;
________________________________________________________
→ can be expressed as " 3x: 2x" ;

in which the total number of students is: " 3x + 2x " = 5x " .

→ The total number of students is represented as: " 5x " .
________________________________________________________
→ The ratio of "girls to boys" is: "2x : 3x" .

→ {that is; the "inverse" of the ratio of "boys to girls"} ;
→ {that is; the "inverse" of " 3x: 2x" } ; → which is: " 2x : 3x " .
________________________________________________________

The ratio of "girls" to "all students" is: "2x : 5x " ; or " 2x/5x " ;
→ Both "x" values cancel ; {since: " x/x = 1 "} ;
_________________________________________________________
→ and we have the answer: " 2 :5 " ; or, write as: " 2/5 " .
_________________________________________________________
The ratio of 'girls' to 'all students' is: " 2 :5 " ; or, write as: " 2/5 ".
_________________________________________________________

8 0

2 years ago

The table shows the solution to the equation |2x − 5| − 2 = 3: Step 1 |2x − 5| = 3 + 2 Step 2 |2x − 5| = 5 Step 3 2x − 5 = 5 or

telo118 [61]

|2x − 5| − 2 = 3
1) |2x − 5| = 3 +2
2) |2x − 5| = 5
3) 2x-5 = 5, or 2x-5= -5
4)2x=10, or 2x=0
5) x = 5 , or x = 0

Check:
 |2x − 5| − 2 = 3
|2*5− 5| − 2 = 3 or |2*0 − 5| − 2 = 3
|5|-2=3 or |-5| -2 =3
3=3 (true) or 3=3 (true)

All steps are correct.

3 0

2 years ago