A senatorial candidate had planned to visit seven cities prior to a primary election. However, he could only visit four of the cities. How many different itineraries could be considered?
A
640
B
840
C
520
D
920
Verified Correct Answer: B.
Step-by-Step Mathematical Solution
Number of itineraries = 7P4
= \(\frac{7!}{(7-4)!}\)
=\(\frac{7!}{3!}\)
=\(\frac{7 \times 6 \times 5 \times 4 \times 3!}{3!}\)
= 840
Source: Myschool Past Questions Archive (Record #9144)