We can find the answer by taking the total count of time, 150, and subtract 24 from it. This is because the 24 minute introduction is not part of the performances, so it is not part of our equation. After we subtract the two numbers to get 126, we divide the remaining number by 6. This is because each performance lasts 6 minutes, so by dividing it from 126, we get the total amount of performances. The answer is 21.
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