Answer:
- <u><em>P(M) = 0.4</em></u>
Explanation:
<u>1. Build a two-way frequency table:</u>
To have a complete understanding of the scenary build a two-way frequency table.
Major in math No major in math Total
Major in CS
No major in CS
Total
Major in math No major in math Total
Major in CS
No major in CS
Total 200
- <u>80 plan to major in mathematics:</u>
Major in math No major in math Total
Major in CS
No major in CS
Total 80 200
- <u>100 plan to major in computer science</u>:
Major in math No major in math Total
Major in CS 100
No major in CS
Total 80 200
- <u>30 plan to pursue a double major in mathematics and computer science</u>:
Major in math No major in math Total
Major in CS 30 100
No major in CS
Total 80 200
- <u>Complete the missing numbers by subtraction</u>:
Major in math No major in math Total
Major in CS 30 70 100
No major in CS 100
Total 80 120 200
Major in math No major in math Total
Major in CS 30 70 100
No major in CS 50 50 100
Total 80 120 200
<u>2. What is P(M), the probability that a student plans to major in mathematics?</u>
- P(M) = number of students who plan to major in mathematics / number of students
The answer is 7x = 6(x + 15)
x - Jim's rate
y - Pete's rate
<span>Jim completed half the floor in 7 hours: 7x = half of the floor
</span><span>Pete completed the other half of the floor in 6 hours: 6y = half of the floor
So: 7x = 6y
</span><span>Pete can lay 15 more tiles per hour than Jim: y = x + 15
</span>7x = 6y
y = x + 15
Substitute the second equation into the first one:
7x = 6(x + 15)
