30 girls and 42 boys so idk this makes no sense and I'm older than you
Answer:
b. It will decrease by a factor of 2
Step-by-step explanation:
In a sample with a number n of people surveyed with a probability of a success of
, and a confidence interval
, we have the following confidence interval of proportions.

In which
z is the zscore that has a pvalue of
.
The lower end of the interval is given by:

The upper end of the interval is given by:

The length of the interval is the subtraction of the upper end by the lower end, so it is:

This means that the length is inverse proportional to the square root of the size of the sample.
So, if the sample size is multiplied by 4, the length of the interval is going to decrease by a factor of 2.
I would love to use substitution (It is simplier that way I guess)
solve your system of equations.
x+2y=−1;x−y=5
Solve x+2y=−1 for x:
x+2y+−2y=−1+−2y(Add -2y to both sides)
x=−2y−1
Substitute (−2y−1) for x in x−y=5:
x−y=5
−2y−1−y=5
−3y−1=5(Simplify both sides of the equation)
−3y−1+1=5+1(Add 1 to both sides)
−3y=6
−3y/−3 = 6/−3(Divide both sides by -3)
y=−2
Substitute (−2) for y in x=−2y−1:
x=−2y−1
x=(−2)(−2)−1
x=3(Simplify both sides of the equation)
So the answer is (x = 3 and y = -2)
Thank you sooo much Maddi441
Answer:
C
Step-by-step explanation:
The ratio is 1:4 so 1 of the object equals 4 of the scale drawing
30*4=120^2 cm