High School

Roxie evaluated [tex]116 \times 5[/tex] as follows:

\[116 \times 5 = 116 \times \frac{10}{2}\]

\[= 58 \times 10\]

\[= 580.\]

Answer :

Roxie's method to evaluate [tex]116 \times 5[/tex] is a creative approach that uses basic number properties to simplify the calculation. Let's break down her steps:

  1. Initial Expression: [tex]116 \times 5[/tex]

  2. Rewriting the Multiplier: Roxie rewrites 5 as a fraction: [tex]\frac{10}{2}[/tex]. This is a common mathematical technique to make calculations easier. It works because multiplying by [tex]\frac{10}{2}[/tex] is equivalent to multiplying by 5.

    [tex]116 \times 5 = 116 \times \frac{10}{2}[/tex]

  3. Simplifying with Division: Next, Roxie first divides [tex]116[/tex] by [tex]2[/tex] to get [tex]58[/tex]. This step simplifies the calculation by breaking it into smaller steps.

    [tex]116 \times \frac{1}{2} = 58[/tex]

  4. Final Multiplication: Now that the expression is [tex]58 \times 10[/tex], she multiplies [tex]58[/tex] by [tex]10[/tex]. Multiplying by 10 is straightforward because it just involves adding a zero to the end of the number:

    [tex]58 \times 10 = 580[/tex]

By following these steps, Roxie confirms that her simplification and calculation are correct. This method can be helpful because it reduces the complexity of the calculation to smaller, more manageable numbers. In general, thinking flexibly about numbers can often make arithmetic easier and more intuitive.