Subtract 9/70 from 81/60, Solve 1 21/60

Subtract 9/70 from 81/60

1^st number: 1 21/60, 2^nd number: 9/70

81/60 - 9/70 is 171/140.

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,
81/60 = 81 × 7/60 × 7 = 567/420
Likewise, for the 2nd fraction, since 70 × 6 = 420,
9/70 = 9 × 6/70 × 6 = 54/420
Subtract the two like fractions:
567/420 - 54/420 = 567 - 54/420 = 513/420
After reducing the fraction, the answer is 171/140
In mixed form: 131/140

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