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.
D) a numerical expressions
I hope it's help you...
Thanks♥♥
Let x be number of black markers
4.5x + 2x3.25x + 3x1.98x = 284.24
16.94x = 284.24
x = 16.78 = 17
The person bought 17 black pens, 34 red and 51 green