SOLUTION: pleas, solve me 1) if nP5=6720 find n 2) solve equation for n nP3=210 thank you for your helping us

Those 5 factors on the left average to the middle one n-2, 
so the left side isn't far from 

So the solution to

 

should be close to the correct answer,







So we try 8






n = 8
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These 3 factors on the left average to the middle one n-1, 
so the left side isn't far from 

So the solution to

 

should be close to the correct answer,







So we try 7






n = 7

Edwin