The word OPERATE has 7 letters:
O - P - E - R - A - T - E
Counting the frequency of each letter:
- O → 1 time
- P → 1 time
- E → 2 times
- R → 1 time
- A → 1 time
- T → 1 time
The letter E appears twice, while all other letters appear once.
For permutations with repetition, the formula is:
Number of arrangements=r1!×r2!×...n!
where n is the total number of letters and r1,r2,... are the frequencies of repeated letters.
For OPERATE:
Number of arrangements=2!7!
=2×17×6×5×4×3×2×1
=25040
=2520
Therefore, the letters of the word OPERATE can be arranged in 2520 different ways.