Answer:




Step-by-step explanation:
The probability mass function P(X = x) is the probability that X happens x times.
When n trials happen, for each
, the probability mass function is given by:

In which p is the probability that the event happens.
is the permutation of n elements with x repetitions(when there are multiple events happening(like one passes and two not passing)). It can be calculated by the following formula:

The sum of all P(X=x) must be 1.
In this problem
We have 3 trials, so 
The probability that a wafer pass a test is 0.7, so 
Determine the probability mass function of the number of wafers from a lot that pass the test.




Hi,
The sum of ten and a number.
Usually AND refers to adding, that's just the rules of math according to writing equation. Times would be multiplying, taking away is subtraction and divided by is dividing.
So if the question uses AND, it's adding.
A
Answer:
0 and 4
Step-by-step explanation:
Let's call the two numbers a and b. So we know that the difference of the two numbers is 36:
a - b = 36
And we know that their sum is 286:
a + b = 286
We can use either of these equations to solve for one of the variables in terms of the other variable. Let's use the first and solve for a:
a - b = 36
a = 36 + b
Now we plug this into the other equation and solve for b there:
(36 + b) + b = 286
36 + 2b = 286
2b = 250
b = 125
Answer: Yes the ladder will reach the fire
Step-by-step explanation: Please refer to the attached diagram for details.
The fire is at point A, while the top of the truck is at point C. The fire is actually burning at 22 feet off the ground, but because the fire truck itself is already 6 feet off the ground, the point that would serve as the base of the building would be 16 feet from the third floor (which is 22 feet minus 6 feet). Hence, point A to point B is 16 feet. So we need to calculate if line AC (from the truck to the fire at the third floor, labeled as b) shall equal the length of the ladder which is 16-foot long.
The angle of the ladder with the top of the truck is 75 degrees. Therefore,
Sin 75 = opposite/hypotenuse
Sin 75 = 16/b
By cross multiplication we now have
b = 16/Sin 75
b = 16/0.9659
b = 16.56
If the distance from A to C is 16.56 feet, then the 16-foot long ladder would reach the fire.