We are given: The number of bands in the chicken soup county battles of the bands = 40.
The percentage of the all virus state finals will compete = 15% of the total number of bands given.
We have given 40 number of bands.
Therefore, the bands will compete in the finals = 15% of 40.
15% can be written as 0.15.
Therefore, 15% of 40 = 0.15 × 40 = 6.
Therefore, 6 bands will compete in the finals.