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: y=7,x=3
Steps:
y = 2x + 1
3x + y = 16
Substitute y = 2x + 1
3x + 2x + 1 = 16
Simplify
5x+1=16
Isolate x for 5x + 1 = 16: x = 3
For y = 2x + 1
Substitute x = 3
y = 2 · 3 + 1
Simplify
y = 7
The solutions to the system of equations are:
y = 7, x = 3
Hope This Helps!
13 x 6 = 78 it cant be multiplied anymore so it can go into 80 about 6 times.
You might have made an error the first time you solved for x. I got x = -0.5.
When you have your log base 4, the way you cancel that out is by making 4 the base on both sides, so you get 4^(log4) to reduce to 1, and you're left with:
2x + 3 = 4^(1/2) ... Simplify
2x + 3 = 2
2x = -1
x = -1/2
If you plug that back in, everything checks out. Maybe double check your use of logarithm/exponent properties?
Solution :
Let A = Economics, B = Mathematics
n(A) = 311, n(B) = 243, 
a). So, 
= 311 + 243 - 135
= 419
b). n(A only) = 311 - 135
= 176
n(B only) = 243 - 135
= 108
Exactly one of these two courses

= 0.568
c). Neither economics nor mathematics


= 0.162