Answer:
0.8041
Step-by-step explanation:
We know that
μ=72 and σ=5
and P(65<X<78)
We can determine the Z value as (X-μ)/σ
P( 65<X<78 )=P( 65-72< X-μ<78-72)


To fine the Z values:

From the standard normal tables:

to find P ( Z<-1.4)

From the standard normal tables:

Therefore


The answer is B
Have a good day!
Answer:
9/2π cm/s
Step-by-step explanation:
Volume of the spherical balloon V= 4/3πr³
Rate of change of volume dV/dt = dV/dr * dr/dt
dV/dr = 3(4/3πr²)
dV/dr = 4πr²
dV/dr = 4π(2)²
dV/dr = 16π
If V = 72cm²/s
72 = 16π*dr/dt
dr/dt = 72/16π
dr/dt = 9/2π cm/s
Hence the radius is changing at 9/2π cm/s
First find the amount of the difference between the original price and the current price:
$10,600 - $7,400 = $3,200
Divide the difference by the original price:
3200 / 7400 = 0.4324 = 43.2% increase.
Pick a value for 'x' then solve for the 'y'
Ex: X=6 then 6-2y=2 then 4=2y then y=2y
So your answer will be 6,2.
Another answer to your question would be 4,1.