What is [tex]$1.\overrightarrow{7}$[/tex] expressed as a fraction in simplest form?

A. [tex]\frac{16}{9}[/tex]
B. [tex]\frac{25}{9}[/tex]
C. [tex]\frac{8}{7}[/tex]
D. [tex]\frac{13}{7}[/tex]



Answer :

To express [tex]\( 1.\overline{7} \)[/tex] as a fraction in simplest form, follow these steps:

1. Identify the repeating decimal: The repeating part of the decimal is [tex]\( 0.\overline{7} \)[/tex].

2. Express the repeating decimal as a fraction:
- Let [tex]\( x = 0.\overline{7} \)[/tex].
- This means [tex]\( x = 0.7777\ldots \)[/tex].

3. Eliminate the repeating part by multiplying:
- Multiply both sides of the equation by 10 (since the repeating block is one digit long).
- [tex]\( 10x = 7.7777\ldots \)[/tex].

4. Subtract the original equation from this new equation:
- Subtract [tex]\( x = 0.7777\ldots \)[/tex] from [tex]\( 10x = 7.7777\ldots \)[/tex].
- This gives [tex]\( 10x - x = 7.7777\ldots - 0.7777\ldots \)[/tex] or [tex]\( 9x = 7 \)[/tex].

5. Solve for [tex]\( x \)[/tex]:
- [tex]\( x = \frac{7}{9} \)[/tex].

6. Combine the non-repeating and repeating parts:
- We initially started with [tex]\( 1.\overline{7} \)[/tex].
- This can be written as: [tex]\( 1 + 0.\overline{7} \)[/tex].

7. Add together:
- Replace [tex]\( 0.\overline{7} \)[/tex] with the fraction [tex]\(\frac{7}{9}\)[/tex].
- Therefore, it becomes: [tex]\( 1 + \frac{7}{9} \)[/tex].

8. Convert to a single fraction:
- Express 1 as a fraction with the same denominator: [tex]\( 1 = \frac{9}{9} \)[/tex].

- So, [tex]\( 1 + \frac{7}{9} = \frac{9}{9} + \frac{7}{9} = \frac{16}{9} \)[/tex].

Thus, the fraction equivalent to [tex]\( 1.\overline{7} \)[/tex] in simplest form is [tex]\( \frac{16}{9} \)[/tex].

Therefore, the correct answer is:
[tex]\[ \frac{16}{9} \][/tex]