Answer:
The probability that an elementary or secondary school teacher selected at random from this city is a female or holds a second job is 0.90.
Step-by-step explanation:
Denote the events as follows:
<em>X</em> = an elementary or secondary school teacher from a city is a female
<em>Y</em> = an elementary or secondary school teacher holds a second job
The information provided is:
P (X) = 0.66
P (Y) = 0.46
P (X ∩ Y) = 0.22
The addition rule of probability is:

Use this formula to compute the probability that an elementary or secondary school teacher selected at random from this city is a female or holds a second job as follows:

Thus, the probability that an elementary or secondary school teacher selected at random from this city is a female or holds a second job is 0.90.
Answer:
The number of trees in each row is 21.
Step-by-step explanation:
Let us assume the number of trees in each row = m
So, the number of rows in the orchard = Number of trees in each row + 10
or, total number of trees in each row = (10 +m)
Now, Total number of Trees = Number of Rows x Number of trees in 1 row
⇒ 651 = m (m + 10)

⇒ (m +31) = 0, or (m-21) = 0
⇒ m= -31, or m = 21
Now, as m = The number of trees in each row, so m ≠ -31
So, m = 21
Hence, the number of trees in each row is m = 21.
It is given that there are 41 males and 48 females in the small school.
So, the number of ways a male student can be chosen from 41 males is 
Likewise, the number of ways a female student can be chosen from 48 females is
.
Thus, the total number of ways in which 2-person combinations are possible to represent the student body at the PTSAC meetings will be given by:

Answer:
ok639010 is the answer of the day when I am in the toilet

Expanding the left side gives

which gives two solutions,

and

. But if

, then

, but this number isn't real, so

is an extraneous solution. Meanwhile if

, you get

, so this solution is correct.
"Potential solutions" might refer to both possibilities, but there is only one actual (real) solution.