Final answer:
The number of combinations of four pieces out of ten for the concert is 5040.
Step-by-step explanation:
The number of combinations of four pieces out of ten can be found using the concept of permutations. We can use the formula for permutations of n objects taken r at a time, which is given by nPr = n! / (n-r)!, where n is the total number of objects and r is the number of objects to be chosen. In this case, n = 10 and r = 4.
So, the number of combinations of four pieces out of ten is 10P4 = 10! / (10-4)! = 10! / 6! = 10 * 9 * 8 * 7 = 5040.
Therefore, there are 5040 possible combinations of pieces that can be played in the concert.