Using the Pythagorean theorem:
x^2 + (x-2)^2 = (√20)^2
Simplify the right side:
x^2 + (x-2)^2 = 20
Subtract 20 from both sides:
x^2 + (x-2)^2 - 20 = 0
Factor:
(x-4)(x+2) = 0
Solve for each x:
x = 4 and x = -2
The side cant be a negative value, so the answer would be x = 4
The answer is B.
Answer:
a) The mean number of radioactive atoms that decay per day is 81.485.
b) 0% probability that on a given day, 50 radioactive atoms decayed.
Step-by-step explanation:
Poisson distribution:
In a Poisson distribution, the probability that X represents the number of successes of a random variable is given by the following formula:

In which
x is the number of sucesses
e = 2.71828 is the Euler number
is the mean in the given interval.
a. Find the mean number of radioactive atoms that decayed in a day.
29,742 atoms decayed during 365 days, which means that:

The mean number of radioactive atoms that decay per day is 81.485.
b. Find the probability that on a given day, 50 radioactive atoms decayed.
This is P(X = 50). So

0% probability that on a given day, 50 radioactive atoms decayed.
Answer:
First brand of antifreeze: 21 gallons
Second brand of antifreeze: 9 gallons
Step-by-step explanation:
Let's call A the amount of first brand of antifreeze. 20% pure antifreeze
Let's call B the amount of second brand of antifreeze. 70% pure antifreeze
The resulting mixture should have 35% pure antifreeze, and 30 gallons.
Then we know that the total amount of mixture will be:

Then the total amount of pure antifreeze in the mixture will be:


Then we have two equations and two unknowns so we solve the system of equations. Multiply the first equation by -0.7 and add it to the second equation:



+

--------------------------------------



We substitute the value of A into one of the two equations and solve for B.


Answer:
Answer is 4/25
Step-by-step explanation:
0.16*100 = 16 which would allow us to say 16/100
now you can divide 16 and 100 by 4 which would be
16/4 = 4 and 100/4= 25
therefore the answer is 4/25
Set 1 mean - 23.625
Set 2 mean - 23.5
Set 1 median - 23.5
Set 2 median - 22.5
This shows the answer is D :)