Add 72/42 and 84/80
1st number: 1 30/42, 2nd number: 1 4/80
72/42 + 84/80 is 387/140.
Steps for adding 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,
72/42 = 72 × 40/42 × 40 = 2880/1680 - Likewise, for the 2nd fraction, since 80 × 21 = 1680,
84/80 = 84 × 21/80 × 21 = 1764/1680 - Add the two like fractions:
2880/1680 + 1764/1680 = 2880 + 1764/1680 = 4644/1680 - 4644/1680 simplified gives 387/140
- So, 72/42 + 84/80 = 387/140
In mixed form: 2107/140
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Related: 72/84+84/80