A church has 10 bells in its bell tower. before each church service 3 bells are rung in sequence. no bell is rung more than once. how many sequences are there?

To solve this problem you must apply the proccedure shown below:
 1. You must apply the following Permutation formula:

 nPr=n!/(n-r)!

 Where n=8 and r=3

 2. Therefore, you have:

 n!=8!=8x7x6x5x4x3x2x1=40320
 (n-r)!=(8-3)!=5!=5x4x3x2x1=120

 3. Then, when you substitute this values into the formula shown above, you obtain:

  nPr=n!/(n-r)!
 nPr=40320/120=336

 4. Therefore, as you can see, the answer is: 336