Subtract 42/7 from 7/21
1st number: 7/21, 2nd number: 6 0/7
7/21 - 42/7 is -17/3.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 7 is 21
Next, find the equivalent fraction of both fractional numbers with denominator 21 - For the 1st fraction, since 21 × 1 = 21,
7/21 = 7 × 1/21 × 1 = 7/21 - Likewise, for the 2nd fraction, since 7 × 3 = 21,
42/7 = 42 × 3/7 × 3 = 126/21 - Subtract the two like fractions:
7/21 - 126/21 = 7 - 126/21 = -119/21 - After reducing the fraction, the answer is -17/3
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