Answers

Subtract 3/9 from 1/7

1/7 - 3/9 is -4/21.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 7 and 9 is 63
2. For the 1st fraction, since 7 × 9 = 63,
   1/7 = 1 × 9/7 × 9 = 9/63
3. Likewise, for the 2nd fraction, since 9 × 7 = 63,
   3/9 = 3 × 7/9 × 7 = 21/63
4. Subtract the two fractions:
   9/63 - 21/63 = 9 - 21/63 = -12/63
5. After reducing the fraction, the answer is -4/21

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