Add 81/42 and 12/40
1st number: 1 39/42, 2nd number: 12/40
81/42 + 12/40 is 78/35.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 40 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 42 × 20 = 840,
81/42 = 81 × 20/42 × 20 = 1620/840 - Likewise, for the 2nd fraction, since 40 × 21 = 840,
12/40 = 12 × 21/40 × 21 = 252/840 - Add the two like fractions:
1620/840 + 252/840 = 1620 + 252/840 = 1872/840 - 1872/840 simplified gives 78/35
- So, 81/42 + 12/40 = 78/35
In mixed form: 28/35
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