Subtract 21/80 from 84/54, Solve 1 30/54

Subtract 21/80 from 84/54

1^st number: 1 30/54, 2^nd number: 21/80

84/54 - 21/80 is 931/720.

Find the least common denominator or LCM of the two denominators:
LCM of 54 and 80 is 2160

Next, find the equivalent fraction of both fractional numbers with denominator 2160
For the 1st fraction, since 54 × 40 = 2160,
84/54 = 84 × 40/54 × 40 = 3360/2160
Likewise, for the 2nd fraction, since 80 × 27 = 2160,
21/80 = 21 × 27/80 × 27 = 567/2160
Subtract the two like fractions:
3360/2160 - 567/2160 = 3360 - 567/2160 = 2793/2160
After reducing the fraction, the answer is 931/720
In mixed form: 1211/720

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