(This is what I think) First, we minus 720 from her 1000. Now she has $280 left. 280 divided by 28 (the trainer cost) is 10. So, she can spend 10 hours with the personal trainer.
Answer:
165
Step-by-step explanation:
180-15=165
The quick way to get the answer is just type "42 choose 11" into Google.
Or if you want to figure it out yourself, you have 42 choices for the first potential juror, 41 choices for the second potential juror, etc.
Now before you stop there, you only care about the combination of the 11 people chosen, not what order they are selected, so you need to divide by the ways to arrange 11 people.
Final expression:
C(42,11) = (42 * 41 * 40 * 39 * 38 * 37 * 36 * 35 * 34 * 33 * 32) / (11 * 10 * 9 * 8 * 7 * 6 * 5 * 4 * 3 * 2 * 1)
Answers:
4,280,561,376 ways
