Answer:
a. 120
b. 6
c. 0.05
Step-by-step explanation:
a) The ways Eduardo, Sarah, Maria, Jim, and Tyrone can arrive to the party is
5! = 5×4×3×2×1 = 120
The logic behind it is
- 5 different people can arrive first, after that
- 4 different people can arrive second, when first and second arrived is known,
- 3 different people can arrive third, then
- 2 different people can arrive fourth
- only 1 person left to be fifth.
b) Using the same logic, when first and last arrived is known, there is
3!=3×2×1=6 ways they can arrive in this case.
c) The probability that Eduardo will arrive first and Tyrone last is
the division of the ways Eduardo arrive first and Tyrone last by the ways 5 people can arrive