Subtract 4/70 from 81/30, Solve 2 21/30

Subtract 4/70 from 81/30

1^st number: 2 21/30, 2^nd number: 4/70

81/30 - 4/70 is 37/14.

Find the least common denominator or LCM of the two denominators:
LCM of 30 and 70 is 210

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 30 × 7 = 210,
81/30 = 81 × 7/30 × 7 = 567/210
Likewise, for the 2nd fraction, since 70 × 3 = 210,
4/70 = 4 × 3/70 × 3 = 12/210
Subtract the two like fractions:
567/210 - 12/210 = 567 - 12/210 = 555/210
After reducing the fraction, the answer is 37/14
In mixed form: 29/14

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