Astudent forgot to include the 12 h2o when calculating the formula mass of the compound. how will the calculated percent yield be affected?

If the student forgot to calculate 12 H2O molecule from the compound, that means the compound molecular mass used will be much lower than it should. If the molecular mass calculated lower than it should, then the percent yield would be increased.
If the student fixes the compound mass, then the yield will become lower than the first result.