Step-by-step explanation:
Assuming the data is as shown, restaurant X has a mean service time of 180.56, with a standard deviation of 62.6.
The standard error is SE = s/√n = 62.6/√50 = 8.85.
At 95% confidence, the critical value is z = 1.960.
Therefore, the confidence interval is:
180.56 ± 1.960 × 8.85
180.56 ± 17.35
(163, 198)
Restaurant Y has a mean service time of 152.96, with a standard deviation of 49.2.
The standard error is SE = s/√n = 49.2/√50 = 6.96.
At 95% confidence, the critical value is z = 1.960.
Therefore, the confidence interval is:
152.96 ± 1.960 × 6.96
152.96 ± 13.64
(139, 167)
Sorry we can’t help with this
Answer:

Step-by-step explanation:
Given;
x² - 2x - 1 = 0
Solve by completing the square method;
⇒ take the constant to the right hand side of the equation.
x² - 2x = 1
⇒ take half of coefficient of x = ¹/₂ x -2 = -1
⇒ square half of coefficient of x and add it to the both sides of the equation


⇒ take the square root of both sides;

Therefore, option B is the right solution.
The total amount of angles in quadrilateral is 360.so:
z=360-(122+79+90)
z=360-291
z=69
Answer:
25%
Step-by-step explanation:
Discount = 1600 - 1200 = 400
Percentage discount
