Add 72/20 and 81/7
1st number: 3 12/20, 2nd number: 11 4/7
72/20 + 81/7 is 531/35.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 7 is 140
Next, find the equivalent fraction of both fractional numbers with denominator 140 - For the 1st fraction, since 20 × 7 = 140,
72/20 = 72 × 7/20 × 7 = 504/140 - Likewise, for the 2nd fraction, since 7 × 20 = 140,
81/7 = 81 × 20/7 × 20 = 1620/140 - Add the two like fractions:
504/140 + 1620/140 = 504 + 1620/140 = 2124/140 - 2124/140 simplified gives 531/35
- So, 72/20 + 81/7 = 531/35
In mixed form: 156/35
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