Subtract 81/70 from 30/60, Solve 30/60

Subtract 81/70 from 30/60

1^st number: 30/60, 2^nd number: 1 11/70

30/60 - 81/70 is -23/35.

Find the least common denominator or LCM of the two denominators:
LCM of 60 and 70 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 60 × 7 = 420,
30/60 = 30 × 7/60 × 7 = 210/420
Likewise, for the 2nd fraction, since 70 × 6 = 420,
81/70 = 81 × 6/70 × 6 = 486/420
Subtract the two like fractions:
210/420 - 486/420 = 210 - 486/420 = -276/420
After reducing the fraction, the answer is -23/35

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