Subtract 81/80 from 3/45, Solve 3/45

Subtract 81/80 from 3/45

1^st number: 3/45, 2^nd number: 1 1/80

3/45 - 81/80 is -227/240.

Find the least common denominator or LCM of the two denominators:
LCM of 45 and 80 is 720

Next, find the equivalent fraction of both fractional numbers with denominator 720
For the 1st fraction, since 45 × 16 = 720,
3/45 = 3 × 16/45 × 16 = 48/720
Likewise, for the 2nd fraction, since 80 × 9 = 720,
81/80 = 81 × 9/80 × 9 = 729/720
Subtract the two like fractions:
48/720 - 729/720 = 48 - 729/720 = -681/720
After reducing the fraction, the answer is -227/240

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