Answer: The manager is incorrect.
Step-by-step explanation: 500,000 nails/500 nails = 1,000 nails. If a survery of 500 nails finds 4 misshapen ones, we must multiply 4 by 1,000 because multiplying 500 by 1,000 gives us 500,000. 4x1,000+4,000. 4,000 does not equal 1,500, so the manager is incorrect.