Answer: 505
Step-by-step explanation:
The formula to find the sample size n , if the prior estimate of the population proportion (p) is known:
, where E= margin of error and z = Critical z-value.
Let p be the population proportion of crashes.
Prior sample size = 250
No. of people experience computer crashes = 75
Prior proportion of crashes 
E= 0.04
From z-table , the z-value corresponding to 95% confidence interval = z=1.96
Required sample size will be :
(Substitute all the values in the above formula)
(Rounded to the next integer.)
∴ Required sample size = 505
We can get two different equations from this:
3x = 18
and
3x = -18
So:
x = 6, x = -6
x = {6, -6}
Answer:
y = 7/2x -11/2
Step-by-step explanation:
7x-2y=11
Subtract 7x from each side
7x-2y -7x = -7x+11
-2y = -7x+11
Divide each side by -2
-2y/-2 = -7x/-2 +11/-2
y = 7/2x -11/2
Answer:
A quadratic equation is second degree equation with the standard form ax^2+bx+c=0 as the highest power is 2.
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Answer:
28 white strands , 20 blue strands and 32 red strands are needed to make a pair of pom-poms
Step-by-step explanation:
Given :A pom-pom manufacturer makes each of its pom-poms with 35% white strands (w), 25% blue strands (b), and 40% red strands (r).
To Find : If each pom-pom has a total of 80 strands, how many of strands of each color are needed to make a pair of pom-poms?
Solution:
Total Strands = 80
White Strands = 35%
No. of white strands = 
Blue Strands = 25%
No. of blue strands = 
Red Strands = 40%
No. of Red strands = 
Hence 28 white strands , 20 blue strands and 32 red strands are needed to make a pair of pom-poms
