Four out of 9 performers will be chosen to stand in a row on stage. How many ways can the 4 performers stand in a row? A. 362,880 ways B. 347,760 ways C. 15,120 ways D. 3024 ways
In the first one there can be 1 out of 9 performers. In the second - 1 out of 8 (because one has been already chosen). In the third - 1 out of 7 (because two have been selected). In the forth - 1 out of 6 (because three are already on the stage).
Total number of combinations is equal to: 9x8x7x6 = 3024
