4 of 8 The following are the ages (years) of 5 people in a room:
25, 22, 13, 14, 21
A person enters the room.
The mean age of the 6 people is now 22.
What is the age of the person who entered the room?
I
years

Step-by-step explanation:

First add all of the numbers together

25+22+13+14+21=82

Now add a variable like X since we don't know the age of the sixth, and divide it by 6 since there are 6 people in the class.

82+X/6=22

(22 is the mean age)

Now solve for the equation

82+X=132

so X =50

85.560%

step-by-step explanation:

conditional probability is defined as:

p(a|b) = p(a∩b) / p(b)

in other words, the probability that a occurs, given that b has occurred = the probability that both a and b occur / the probability that b occurs.

in this example:

p(turns 64 | turns 44) = p(turns 64 & turns 44) / p(turns 44).

if someone turns 64, they must have already turned 44, so:

p(turns 64 | turns 44) = p(turns 64) / p(turns 44)

on page 42, we see that of the original 100,000, 94944 turn 44, and 81234 turn 64.   therefore:

p(turns 64 | turns 44) = 81234 / 94944

p(turns 64 | turns 44) = 0.85560