Q. Write the repeating decimal as a fraction..212212212
Identify Repeating Pattern: Let's identify the repeating pattern in the decimal. The digits "212" repeat indefinitely.
Express as Sum: Express the repeating decimal as a sum of its parts: 0.212212212...=0.212+0.000212+0.000000212+…
Convert to Fraction: Convert each part into a fraction: 0.212=1000212, and notice that each subsequent part is 1000 times smaller than the previous one.
Recognize Geometric Series: Recognize that this is a geometric series with the first term a1=1000212 and the common ratio r=10001.
Use Sum Formula: Use the formula for the sum of an infinite geometric series, S=1−ra1, where S is the sum, a1 is the first term, and r is the common ratio.
Substitute Values: Substitute the values into the formula: S=1000212/(1−10001).
Simplify Denominator: Simplify the denominator: 1−10001=1000999.
Calculate Sum: Now, calculate the sum: S=10009991000212.
Multiply by Reciprocal: Multiply by the reciprocal of the denominator: S=1000212×9991000.
Simplify Fraction: Simplify the fraction by multiplying the numerators and denominators: S=999212.
Simplify Fraction: Simplify the fraction by multiplying the numerators and denominators: S=999212.Check for any possible simplification of the fraction 999212. Since 212 and 999 have no common factors other than 1, the fraction is already in its simplest form.
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