The neutralisation of a 1.20 g solution of a mixture of `H_2C_2O_4.2H_2O` and `KHC_2O_4.H_2O` and different impurities of a neutral salt consumed 37.80 " mL of " 0.25 N NaOH solution. On the other hand, on titration with `KMnO_4` for 0.40 g of the same substance, 43.10 " mL of " 0.125 N `KMnO_4` was required. Find the percentage composition of the substance being analysed.

Explanation

To solve the problem, we need to find the percentage composition of the mixture of oxalic acid dihydrate (H₂C₂O₄·2H₂O) and potassium hydrogen oxalate monohydrate (KHC₂O₄·H₂O) in a 1.20 g sample that was neutralized with NaOH and titrated with KMnO₄.

### Step 1: Define Variables
Let:
- \( A \) = percentage of H₂C₂O₄·2H₂O
- \( B \) = percentage of KHC₂O₄·H₂O

Since the total percentage must equal 100%, we have:
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