OlympiadMediumCombinatorics7–9
The six letters of LISBOA are arranged in a row. In how many arrangements do the three vowels stand together, in consecutive positions?
As seis letras de LISBOA são dispostas numa fila. Em quantas disposições as três vogais ficam juntas, em posições consecutivas?
Answer options
Solution
Step 1 of 3
- 1.Glue the vowels I, O, A into a single block. The row then holds four objects: the block, L, S and B.