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
Slopes of perpendicular lines are opposite reciprocals of each other. The slope of the given equation (which is in slope-intercept form) is 1, the invisible coefficient of x. The opposite reciprocal of 1 is -1, thus the slope of a line perpendicular to the line y = x + 4 is -1.
Hope this helps.
Distributive Property: a ( b + c) = (a*b) + (a*c)
b) x(x + 9) = x*x + 9*x
= x² + 9x
c) x² - 18x
x² = x * x
18x = 18 *x
G C F = x
Greatest common factor in both the terms is 'x'.Take the common variable from both the terms.
x² - 18x = x*x - 18*x
= x (x - 18)
Standard form. Factored form
x² x*x
x² + 9x x(x +9)
x² - 18x x(x - 18)
-x² + 10x x(-x + 10) = x(10 -x)
-x² - 2.75x -x(x + 2.75)
I believe this is right..
10/16= x/100
x=62.5%
100%- 62.5%= 37.5%
