Chapter 5 - Section 5.3 - Multiplying Decimals and Circumference of a Circle - Vocabulary, Readiness & Video Check - Page 359: 1

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For example: $\frac{1}{10}\times\frac{1}{10}=\frac{1}{100}\ \Rightarrow$ $\underbrace{0.1}\times\underbrace{0.1}=\underbrace{0.01}$ $\ \ \ 1\ \ +\ \ 1\ \ =\ \ \ 2$ $\frac{1}{100}\times\frac{1}{100}=\frac{1}{10000}\ \Rightarrow$ $\underbrace{0.01}\times\underbrace{0.01}=\underbrace{0.0001}$ $\ \ \ 2\ \ +\ \ 2\ \ =\ \ \ \ \ 4$