Subtract 1/49 from 81/21, Solve 3 18/21

Subtract 1/49 from 81/21

1^st number: 3 18/21, 2^nd number: 1/49

81/21 - 1/49 is 188/49.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 49 is 147

Next, find the equivalent fraction of both fractional numbers with denominator 147
For the 1st fraction, since 21 × 7 = 147,
81/21 = 81 × 7/21 × 7 = 567/147
Likewise, for the 2nd fraction, since 49 × 3 = 147,
1/49 = 1 × 3/49 × 3 = 3/147
Subtract the two like fractions:
567/147 - 3/147 = 567 - 3/147 = 564/147
After reducing the fraction, the answer is 188/49
In mixed form: 341/49

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