Question

A flask contained 1 L of hot water mrs tey used 2/5 l of the hot water to make a chocolate drink and 1/2 l of hot water to make tea how much hot water was left in the flask

Answer 1

To determine how much hot water is left in the flask, we need to subtract the amounts of hot water used to make the chocolate drink and tea from the original amount of hot water in the flask.

1. **Original amount of hot water**: 1 L
2. **Hot water used for the chocolate drink**: \( \frac{2}{5} \) L
3. **Hot water used for tea**: \( \frac{1}{2} \) L

First, we need to convert these fractions to a common denominator to make the subtraction easier. The least common multiple of 5 and 2 is 10.

- Convert \( \frac{2}{5} \) to tenths:
\[
\frac{2}{5} = \frac{2 \times 2}{5 \times 2} = \frac{4}{10}
\]

- Convert \( \frac{1}{2} \) to tenths:
\[
\frac{1}{2} = \frac{1 \times 5}{2 \times 5} = \frac{5}{10}
\]

Now, add the amounts used for the chocolate drink and tea:
\[
\frac{4}{10} + \frac{5}{10} = \frac{9}{10}
\]

Now, subtract this total from the original amount of hot water:
\[
1 \text{ L} = \frac{10}{10} \text{ L}
\]

So:
\[
\frac{10}{10} - \frac{9}{10} = \frac{1}{10} \text{ L}
\]

Therefore, the amount of hot water left in the flask is \( \frac{1}{10} \) L, or 0.1 L.