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How to multiply fractions (Basic)

Let’s calculate . You can take 3 steps:

  1. Multiply the numerators.
  2. Multiply the denominators.
  3. 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

\begin{eqnarray*} && \frac{ 1 }{ 2 } \times \frac{ 1 }{ 3 } \\ &=& \frac{ 1 \times 1 }{ 2 \times 3 } \\ &=& \frac{ 1 }{ 6 } \end{eqnarray*}

\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*}

How can we multiply fractions? 1. Multiply the numerators. 2. Multiply the denominators. 3. Write a slash. That's all.