Let's calculate . You can take 3 steps:
- Multiply the numerators.
- Multiply the denominators.
- Write a slash.
\begin{eqnarray*} && \frac{ 2 }{ 3 } \times \frac{ 5 }{ 7 } \\ &=& \frac{ 2 \times 5 }{ 3 \times 7 } \\ &=& \frac{ 10 }{ 21 } \end{eqnarray*}
Questions
Answers
1.
\begin{eqnarray*} && \frac{ 1 }{ 2 } \times \frac{ 1 }{ 3 } \\ &=& \frac{ 1 \times 1 }{ 2 \times 3 } \\ &=& \frac{ 1 }{ 6 } \end{eqnarray*}
2.
\begin{eqnarray*} && \frac{ 5 }{ 6 } \times \frac{ 3 }{ 5 } \\ &=& \frac{ 5 \times 3 }{ 6 \times 5 } \\ &=& \frac{ 15 }{ 30 } \end{eqnarray*}
Oh, 15 is a divisor of 30, then .
\begin{eqnarray*} && \frac{ 5 }{ 6 } \times \frac{ 3 }{ 5 } \\ &=& \frac{ 5 \times 3 }{ 6 \times 5 } \\ &=& \frac{ 15 }{ 30 } \\ &=& \frac{ 1 }{ 2 } \end{eqnarray*}
