90-x*30=80
90-30x=80
90-90-30x=80-90
-30x=-10
Divide by -30 for -30x and -10
-30/-30x=-10/-30
x=1/3
As you can see, the area of the scarf is equal to the area of the rectangle minus the area of the 2 semi-circles (which form a circle)
Now, we calculate the area of the rectangle : 28 x 15 = 420 in2
The diameter of the circle is 15in -> The radius = 15 : 2 = 7.5in.
We now find the area of the 2 semi-circles : 7.5 x 7.5 x 3.14 = 176.625 in2
So, the area of the scarf is : 420 - 176.625 = 243.375 in2
Answer:
a. 0.45 customers
b. 0.0145 hours
c. 1.05 customers
Step-by-step explanation:
Missing word "A vending machine dispenses hot chocolate or coffee. service time is 30 seconds per cup and is constant. customers arrive at a mean rate of 72 per hour, and this rate is Poisson-distributed."
λ = 72 customers per hours
μ = 120 customers per hours
a. Lq = λ²/ 2μ(μ-λ)
Lq = 72² / 2(120)(120-72)
Lq = 9/20
Lq = 0.45 customers
b. Ws = Wq + 1/μ = Lq/λ + 1/μ
Ws = 9/20 customers/72 customers + 1/120 customers
Ws = 0.0145 hours
c. Ls = Lq + r
Ls = 9/20 + 72/120
Ls = 1.05 customers
According to the graph the answer is : y = 2.5x + 5