A sample of `Fe(SO_4)_3` and `FeC_2O_4` was dissolved in `H_2SO_4`. 40 " mL of " `(N)/(15)KMnO_4` was required for complete oxidation. After oxidation the mixture was reduced by `(Zn)/(H_2SO_4)`. On again oxidation by same `KMnO_4`, 25 mL was required. Calculate the ratio of fe in "`Fe_2(SO_4)_3` and `FeC_2O_4`.

Explanation

To solve the problem, we need to determine the ratio of iron (Fe) in `Fe2(SO4)3` and `FeC2O4` based on the given information about the oxidation reactions with `KMnO4`.

### Step-by-Step Solution:

1. **Identify the Molar Mass and Equivalent Factors**:
- For `Fe2(SO4)3`:
- Molar mass of `Fe` = 55.85 g/mol
- Molar mass of `SO4` = 96.06 g/mol
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