Question 3
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If all arrangements of the letters of MOTHER are listed in dictionary order, what is the rank of MOTHER?
- A 308
- B 310
- C 309 Correct
- D 240
Correct Answer: Option C
Letters in order: E H M O R T
Starting with E or H: 2 × 5! = 240
M then E or H: 2 × 4! = 48
MO then E, H or R: 3 × 3! = 18
MOT then E: 1 × 2! = 2
MOTHER itself: + 1
Rank = 240 + 48 + 18 + 2 + 1 = 309
Trap: 308 forgets to count the word itself.
Answer: 309
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