Subtract 16/9 from 42/80, Solve 42/80

Subtract 16/9 from 42/80

1^st number: 42/80, 2^nd number: 1 7/9

42/80 - 16/9 is -451/360.

Find the least common denominator or LCM of the two denominators:
LCM of 80 and 9 is 720

Next, find the equivalent fraction of both fractional numbers with denominator 720
For the 1st fraction, since 80 × 9 = 720,
42/80 = 42 × 9/80 × 9 = 378/720
Likewise, for the 2nd fraction, since 9 × 80 = 720,
16/9 = 16 × 80/9 × 80 = 1280/720
Subtract the two like fractions:
378/720 - 1280/720 = 378 - 1280/720 = -902/720
After reducing the fraction, the answer is -451/360

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