1. The problem is to simplify the expression \(\frac{0,(7) + 1}{0,(7) + 2} - \frac{7}{176} \div \frac{0,(81) + 1}{0,(81) + 2}\).
2. First, convert the repeating decimals to fractions.
- For \(0,(7)\), the repeating decimal 0.7777... equals \(\frac{7}{9}\).
- For \(0,(81)\), the repeating decimal 0.818181... equals \(\frac{81}{99} = \frac{9}{11}\).
3. Substitute these into the expression:
\[
\frac{\frac{7}{9} + 1}{\frac{7}{9} + 2} - \frac{7}{176} \div \frac{\frac{9}{11} + 1}{\frac{9}{11} + 2}
\]
4. Simplify the numerators and denominators inside the fractions:
- \(\frac{7}{9} + 1 = \frac{7}{9} + \frac{9}{9} = \frac{16}{9}\)
- \(\frac{7}{9} + 2 = \frac{7}{9} + \frac{18}{9} = \frac{25}{9}\)
- \(\frac{9}{11} + 1 = \frac{9}{11} + \frac{11}{11} = \frac{20}{11}\)
- \(\frac{9}{11} + 2 = \frac{9}{11} + \frac{22}{11} = \frac{31}{11}\)
5. Rewrite the expression:
\[
\frac{\frac{16}{9}}{\frac{25}{9}} - \frac{7}{176} \div \frac{\frac{20}{11}}{\frac{31}{11}}
\]
6. Simplify the complex fractions by multiplying numerator by reciprocal of denominator:
\[
\frac{16}{9} \times \frac{9}{25} - \frac{7}{176} \div \left(\frac{20}{11} \times \frac{11}{31}\right)
\]
7. Cancel common factors:
- \(\frac{16}{\cancel{9}} \times \frac{\cancel{9}}{25} = \frac{16}{25}\)
- \(\frac{20}{11} \times \frac{11}{31} = \frac{20}{\cancel{11}} \times \frac{\cancel{11}}{31} = \frac{20}{31}\)
8. Now the expression is:
\[
\frac{16}{25} - \frac{7}{176} \div \frac{20}{31}
\]
9. Division by a fraction is multiplication by its reciprocal:
\[
\frac{16}{25} - \frac{7}{176} \times \frac{31}{20}
\]
10. Multiply the fractions:
\[
\frac{7 \times 31}{176 \times 20} = \frac{217}{3520}
\]
11. Now the expression is:
\[
\frac{16}{25} - \frac{217}{3520}
\]
12. Find common denominator for subtraction:
- The least common denominator of 25 and 3520 is 3520.
- Convert \(\frac{16}{25}\) to denominator 3520:
\[
\frac{16}{25} = \frac{16 \times 140.8}{25 \times 140.8} = \frac{2252.8}{3520}
\]
Since 140.8 is not an integer, use exact calculation:
\[
3520 \div 25 = 140.8
\]
To avoid decimals, multiply numerator and denominator by 140.8:
\[
\frac{16}{25} = \frac{16 \times 140.8}{25 \times 140.8} = \frac{2252.8}{3520}
\]
Alternatively, multiply numerator and denominator by 1408 and then divide by 10:
\[
25 \times 140.8 = 3520
\]
To keep integers, multiply numerator and denominator by 1408 and then divide numerator by 10:
\[
16 \times 1408 = 22528
\]
So:
\[
\frac{16}{25} = \frac{22528}{35200}
\]
Similarly, convert \(\frac{217}{3520}\) to denominator 35200:
\[
\frac{217}{3520} = \frac{217 \times 10}{3520 \times 10} = \frac{2170}{35200}
\]
13. Now subtract:
\[
\frac{22528}{35200} - \frac{2170}{35200} = \frac{22528 - 2170}{35200} = \frac{20358}{35200}
\]
14. Simplify the fraction \(\frac{20358}{35200}\):
- Both numerator and denominator are divisible by 2:
\[
\frac{\cancel{2}0179}{\cancel{2}17600} = \frac{10179}{17600}
\]
- Check for further simplification:
10179 factors: 1+0+1+7+9=18 divisible by 3, so 10179 divisible by 3.
17600 divisible by 3? Sum digits 1+7+6+0+0=14 not divisible by 3.
So no further simplification.
15. Final simplified answer:
\[
\frac{10179}{17600}
\]
This is the simplified exact value of the original expression.
Simplify Repeating Bd48Bc
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