1. **State the problem:** MRS Duval makes 1 litre of ice cream. She eats $\frac{1}{8}$ litre and her children eat $\frac{3}{5}$ litre. We need to find the fraction of a litre of ice cream left. 2. **Formula and rules:** To find the remaining ice cream, subtract the amounts eaten from the total amount made. $$\text{Remaining} = 1 - \left(\frac{1}{8} + \frac{3}{5}\right)$$ 3. **Find a common denominator:** The denominators are 8 and 5. The least common denominator (LCD) is 40. Convert each fraction: $$\frac{1}{8} = \frac{5}{40}$$ $$\frac{3}{5} = \frac{24}{40}$$ 4. **Add the fractions eaten:** $$\frac{5}{40} + \frac{24}{40} = \frac{29}{40}$$ 5. **Subtract from total:** $$1 - \frac{29}{40} = \frac{40}{40} - \frac{29}{40} = \frac{11}{40}$$ 6. **Answer:** The fraction of a litre of ice cream left is $\frac{11}{40}$ litre.