The answer should be Twenty one
Here is the answer hope this helps
Answer:
y=18 when x=15
Step-by-step explanation:
Answer:
y hat = 2114.20 + 18.96x
Step-by-step explanation:
Given the least square regression model equation:
y hat = -959.00 + 8.60x
weld diameter x ; shear strength y (in pounds)
1 lb = 0.4536 kg
To express shear strength y in kilogram:
y is multiplied by 0.4536
(y hat × 0.4536) = -959.00 + 8.60x
Divide both sides by 0.4536
(y hat × 0.4536) / 0.4536= (-959.00 + 8.60x) / 0.4536
y hat = 2114.1975 + 18.959435x
y hat = 2114.20 + 18.96x
Using the vertex of the quadratic function, it is found that:
a) The maximum number of customers in the store is at 12 P.M.
b) 75 customers are in the store at this time.
The number of customers in x hours after 7 AM is given by:

Which is a quadratic equation with coefficients 
Item a:
The maximum value, considering that a < 0, happens at:

Hence:

5 hours after 7 A.M, hence, the maximum number of customers in the store is at 12 P.M.
Item b:
The value is y(5), hence:

75 customers are in the store at this time.
A similar problem is given at brainly.com/question/24713268