Bala spent $$\frac{2}{5}$$ on a watch, so $$\frac{3}{5}$$ remained. He spent $$\frac{1}{2}$$ of the remainder on a toy.<br><br>[[model:questions/solutions/q4342.png]]<br><br>• Watch → $$\frac{2}{5}$$ of whole = $$\frac{4}{10}$$<br>• Remainder → 1 − $$\frac{2}{5}$$ = $$\frac{3}{5}$$ = $$\frac{6}{10}$$<br>• Toy → $$\frac{1}{2}$$ × $$\frac{6}{10}$$ = $$\frac{3}{10}$$ → 3u<br>• Left → $$\frac{6}{10}$$ − $$\frac{3}{10}$$ = $$\frac{3}{10}$$ → 3u = $15<br>• 1u → $15 ÷ 3 = $5 ⇒ whole 10u → 10 × $5 = $50<br><br>Bala had $50 at first.<br>Check: Watch = $$\frac{2}{5}$$ × 50 = $20. Remainder = $30. Toy = $$\frac{1}{2}$$ × 30 = $15. Left = $15. ✓