Subtract 21/80 from 84/42
1st number: 2 0/42, 2nd number: 21/80
84/42 - 21/80 is 139/80.
Steps for subtracting fractions
- 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,
21/80 = 21 × 21/80 × 21 = 441/1680 - Subtract the two like fractions:
3360/1680 - 441/1680 = 3360 - 441/1680 = 2919/1680 - After reducing the fraction, the answer is 139/80
- In mixed form: 159/80
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