Add 84/7 and 72/20
1st number: 12 0/7, 2nd number: 3 12/20
84/7 + 72/20 is 78/5.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 7 and 20 is 140
Next, find the equivalent fraction of both fractional numbers with denominator 140 - For the 1st fraction, since 7 × 20 = 140,
84/7 = 84 × 20/7 × 20 = 1680/140 - Likewise, for the 2nd fraction, since 20 × 7 = 140,
72/20 = 72 × 7/20 × 7 = 504/140 - Add the two like fractions:
1680/140 + 504/140 = 1680 + 504/140 = 2184/140 - 2184/140 simplified gives 78/5
- So, 84/7 + 72/20 = 78/5
In mixed form: 153/5
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