Four girls: Anna, Bea, Cili, and Dóra, sang songs at their music school exam. Every song was performed by three of them, with the fourth accompanying on the piano. Anna sang the most - a total of eight times, while Dóra sang only five times - the others sang more often than her.

How many songs were performed in total?
If we add up how many songs each of the girls sang, we get a number divisible by 3, since every song was performed by three of them. Bea and Cili did not sing more often than Anna, but both participated in at least 6 song performances as singers, so the above sum falls between $8+6+6+5$ and $8+8+8+5$, which means $25, 26, 27, 28$ or 29.

Among the obtained numbers, 27 is the only one divisible by 3, so the number of songs performed is one-third of this, which is 9.

Nine song performances are also possible under the given conditions, if Anna played the piano once, Bea and Cili twice each, and Dóra four times.