Subtract 18/9 from 81/70, Solve 1 11/70

Subtract 18/9 from 81/70

1^st number: 1 11/70, 2^nd number: 2 0/9

81/70 - 18/9 is -59/70.

Find the least common denominator or LCM of the two denominators:
LCM of 70 and 9 is 630

Next, find the equivalent fraction of both fractional numbers with denominator 630
For the 1st fraction, since 70 × 9 = 630,
81/70 = 81 × 9/70 × 9 = 729/630
Likewise, for the 2nd fraction, since 9 × 70 = 630,
18/9 = 18 × 70/9 × 70 = 1260/630
Subtract the two like fractions:
729/630 - 1260/630 = 729 - 1260/630 = -531/630
After reducing the fraction, the answer is -59/70

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