Subtract 18/84 from 72/30, Solve 2 12/30

Subtract 18/84 from 72/30

1^st number: 2 12/30, 2^nd number: 18/84

72/30 - 18/84 is 153/70.

Find the least common denominator or LCM of the two denominators:
LCM of 30 and 84 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 30 × 14 = 420,
72/30 = 72 × 14/30 × 14 = 1008/420
Likewise, for the 2nd fraction, since 84 × 5 = 420,
18/84 = 18 × 5/84 × 5 = 90/420
Subtract the two like fractions:
1008/420 - 90/420 = 1008 - 90/420 = 918/420
After reducing the fraction, the answer is 153/70
In mixed form: 213/70

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