Question

Which fractions are equivalent to 0.63 repeating?

Answer 1

28/44 is the correct answer

Answer 2

Answers: 21/33 and 28/44

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Work Shown:

`\text{x} = 0.\overline{63}`

x = 0.63636363...

100x = 63.63636363...

100x - x = (63.63636363...) - (0.63636363...)

99x = 63

x = 63/99

x = (7*9)/(11*9)

x = 7/11

This table shows a few fractions equivalent to 7/11

`\begin{array}c \cline{1-2}\text{Multiply top} & \\ \text{and bottom by} & \text{Equivalent fraction}\\\cline{1-2}2 & 14/22\\\cline{1-2}3 & \boldsymbol{21/33}\\\cline{1-2}4 & \boldsymbol{28/44}\\\cline{1-2}5 & 35/55\\\cline{1-2}6 & 42/66\\\cline{1-2}\end{array}`

The terms in bold are the two answers

In other words, 7/11 = 21/33 when multiplying top and bottom by 3.

Also, 7/11 = 28/44 when multiplying top and bottom by 4.

To confirm those answers, use a calculator to find that

7/11 = 0.636363...

21/33 = 0.636363...

28/44 = 0.636363...

To rule out the non-answers, use the calculator to find that

14/21 = 0.667 approximately

7/12 = 0.5833 approximately