Answer:
The probability that a Tech High student fails math is 0.1006
Step-by-step explanation:
21% students are taking class with Mary.
Every year 4% of Mary’s students fail,
15% students are taking class with Tom
Every year 6% of Tom’s students fail.
64% students are taking class with Alex
Every year 13% of Alex's students fail.
Now we are supposed to find the probability that a Tech High student fails math.
[tex]P(\text{Tech High student fails math}) = P(\text{taking class with Mary})\times P(\text{Mary students fail})+P(\text{taking class with Tom}) \times P(\text{Tom students fail})+P(\text{taking class with Alex}) \times P(\text{Alex student fail})[/tex]
[tex]P(\text{Tech High student fails math}) = 0.21 \times 0.04+0.15 \times 0.06+0.64 \times 0.13[/tex]
[tex]P(\text{Tech High student fails math}) =0.1006[/tex]
Hence the probability that a Tech High student fails math is 0.1006