Subtract 56/21 from 30/18, Solve 1 12/18

Subtract 56/21 from 30/18

1^st number: 1 12/18, 2^nd number: 2 14/21

30/18 - 56/21 is -1/1.

Find the least common denominator or LCM of the two denominators:
LCM of 18 and 21 is 126

Next, find the equivalent fraction of both fractional numbers with denominator 126
For the 1st fraction, since 18 × 7 = 126,
30/18 = 30 × 7/18 × 7 = 210/126
Likewise, for the 2nd fraction, since 21 × 6 = 126,
56/21 = 56 × 6/21 × 6 = 336/126
Subtract the two like fractions:
210/126 - 336/126 = 210 - 336/126 = -126/126
After reducing the fraction, the answer is -1/1

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