Answer:
Step-by-step explanation:
Using the formula
p +/- z* √(p(1-p) / n)
Where p is sample proportion = 3226/3957 = 0.8153, n = 3957 and z* is 2.576
0.8153 + (2.576 √(0.8153(1-0.8153) / 3957))
0.8153 + (2.576 √ (0.8153(0.1847) /3957)
0.8513 + (2.576 √(0.1572/3957)
0.8513 + (2.576 √0.00003974)
0.8513 + 2.576(0.0063)
0.8513 + 0.016
0.8670 ~ 87%
For the lower interview
0.8513 - 0.016
= 0.8353 ~ 84%
Thus, at 99% confidence interval is 84% and 87%
Answer:
6 years
Step-by-step explanation:
let x = # of years
6 + 2x = 12 + x
x = 6
Answer:
Step-by-step explanation:
To find the unit rate , divide the total cost by number of books
Cost of 1 book = 26.25 ÷ 3
= $ 8.75
F(x)=... the f(x) is like the y in a regular equation.
Answer:
x = 4
Step-by-step explanation:
Given that sin(13x) = cos(9x+2)
Since sintheta = cos(90 - theta)
hence sin (13x) = cos (90 -13x)
Substitute into the original equation
cos (90 -13x) = cos(9x+2)
90-13x = 9x+2
-13x - 9x = 2 - 90
-22x = -88
x = 88/22
x = 4
Hence the value of x is 4