Subtract 90/80 from 50/42, Solve 1 8/42

Subtract 90/80 from 50/42

1^st number: 1 8/42, 2^nd number: 1 10/80

50/42 - 90/80 is 11/168.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 80 is 1680

Next, find the equivalent fraction of both fractional numbers with denominator 1680
For the 1st fraction, since 42 × 40 = 1680,
50/42 = 50 × 40/42 × 40 = 2000/1680
Likewise, for the 2nd fraction, since 80 × 21 = 1680,
90/80 = 90 × 21/80 × 21 = 1890/1680
Subtract the two like fractions:
2000/1680 - 1890/1680 = 2000 - 1890/1680 = 110/1680
After reducing the fraction, the answer is 11/168

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