Subtract 9/80 from 84/42, Solve 2 0/42

Subtract 9/80 from 84/42

1^st number: 2 0/42, 2^nd number: 9/80

84/42 - 9/80 is 151/80.

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,
84/42 = 84 × 40/42 × 40 = 3360/1680
Likewise, for the 2nd fraction, since 80 × 21 = 1680,
9/80 = 9 × 21/80 × 21 = 189/1680
Subtract the two like fractions:
3360/1680 - 189/1680 = 3360 - 189/1680 = 3171/1680
After reducing the fraction, the answer is 151/80
In mixed form: 171/80

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