Suppose an airline accepted 12 reservations for a commuter plane with 10seats. They know that 7 reservations went to regular commuters who will show up forsure. The other 5 passengers will show up with a 50% chance, independently of eachother.(a) Find the probability that the flight will be overbooked.(b) Find the probability that there will be empty seats.

Step-by-step explanation:

(a)

7 persons will show up for sure, hence there is not any kind of probability here.

The other 5 persons have 50% chance to show up.

The flight will be overbooked, if either 4 will come or 5 will come.

From the total 5 persons, 4 can be chosen in ways.

The probability that any four among the 5 will come is .

The probability that all of the 5 passengers will come is .

Hence, the required probability is .

(b)

The probability that there will be exactly 10 passengers on the flight is .

The probability that there will be no empty seats in the plane is .

Hence, probability of having empty seats is .

answer: ratio of volume of cone (with 3 times the height and equal diameter) to volume of cylinder is 2 to 1. the value of π is not used.

step-by-step explanation:

radius is diameter/2 = 4.

area of circle is π r^2.

volume of cylinder is height × area of base = hπr^2 = 3(4^2) π = 48π cubic inches.

not knowing the formula for volume of cone, i calculate it using calculus (which is for calculating things).

volume of cone is integral 0 to h area(y) dy. area(y) is π r(y)^2. r(y) runs r to zero as y runs zero to h, r(0) = r, r(h) = 0.

r(y) = r - r/h y

area(y) = π (r - r/h y)^2 = π (r^2 - 2r^2y/h + r^2y^2/h^2) = π r^2(1-2y/h+y^2/h^2)

antiderivative area(y) = π r^2 (y-y^2/h+y^3/(3h^2))

integral 0 to h = π r^2(h-h^2/h+h^3/(3h^2) - (0)) = π r^2(h - h + h/3) = π r^2(h/3) = π/3 r^2 h

volume of this cone is π/3(4^2)18 cubic inches.

= 6 16 π = 96π cubic inches.

cone has twice the volume, 96/48.

cone height is 6 times the cylinder.

ratio of volume formula: π r^2 cancels.

cone over cylinder ratio is 6h/3 to h, 2 to 1.