Subtract 3/80 from 54/42, Solve 1 12/42

Subtract 3/80 from 54/42

1^st number: 1 12/42, 2^nd number: 3/80

54/42 - 3/80 is 699/560.

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,
54/42 = 54 × 40/42 × 40 = 2160/1680
Likewise, for the 2nd fraction, since 80 × 21 = 1680,
3/80 = 3 × 21/80 × 21 = 63/1680
Subtract the two like fractions:
2160/1680 - 63/1680 = 2160 - 63/1680 = 2097/1680
After reducing the fraction, the answer is 699/560
In mixed form: 1139/560

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