Answer:The number π is a mathematical constant. Originally defined as the ratio of a circle's circumference to its diameter, it now has various equivalent definitions and appears in many formulas in all areas of mathematics and physics. It is approximately equal to 3.14159.
Step-by-step explanation:
Y=125-20x ; the value of the cell phone after three years is $65.
Answer:
53.15≤x≤67.89
Step-by-step explanation:
The formula for calculating confidence interval is expressed as;
CI = xbar±(z×s/√n)
xbar is the sample mean
z is the z score at 90% CI
s is the standard deviation
n is the sample size
Given
xbar = $60.52
s = $23.29
n = 27
z = 1.645
Substitute into the formula
CI = xbar±(z×s/√n)
CI = 60.52±(1.645×23.29/√27)
CI = 60.52±(1.645×23.29/5.196)
CI = 60.52±(1.645×4.482)
CI = 60.52±7.373
CI = [60.52-7.373, 60.52+7.373]
CI = [53.15, 67.89]
Hence the 90% confidence interval for the mean repair cost for the refrigerators is 53.15≤x≤67.89
Answer:
Graph x2 = 4y and state the vertex, focus, axis of symmetry, and directrix. ... this "algebraically" by rearranging the given equation into the conics form: ... picking y-values first and then finding the corresponding x-values for x = –y2 – 10y – 25: ... find the exact vertex, etc, I'll need to convert the equation to perfect-square form.
Step-by-step explanation:
Answer:
30
Step-by-step explanation:
Because its 30 trust me