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Convert the decimal expansion 0.2777... to a fraction.

User Shijing Lv
by
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1 Answer

6 votes

Answer:

5/18

Explaination:

Let X equal the decimal number

Equation 1:

X=0.2777¯¯¯¯¯¯¯¯(1)

With 3 digits in the repeating decimal group,

create a second equation by multiplying

both sides by 103 = 1000

Equation 2:

1000X=277.7777¯¯¯¯¯¯¯¯(2)

Subtract equation (1) from equation (2)

1000XX999X===277.7777...0.2777...277.5

We get

999X=277.5

Solve for X

X=277.5999

Multiply to eliminate 1 decimal places.

Here you multiply top and bottom by 1 10's

= 101 = 10

277.5999×1010=27759990

Find the Greatest Common Factor (GCF) of 2775 and 9990, if it exists, and reduce the fraction by dividing both numerator and denominator by GCF = 555,

2775÷5559990÷555=518

Therefore

X=518

In conclusion,

0.2777¯¯¯¯¯¯¯¯=518

User Assaf Hershko
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