Add 20/70 and 81/40
1st number: 20/70, 2nd number: 2 1/40
20/70 + 81/40 is 647/280.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 40 is 280
Next, find the equivalent fraction of both fractional numbers with denominator 280 - For the 1st fraction, since 70 × 4 = 280,
20/70 = 20 × 4/70 × 4 = 80/280 - Likewise, for the 2nd fraction, since 40 × 7 = 280,
81/40 = 81 × 7/40 × 7 = 567/280 - Add the two like fractions:
80/280 + 567/280 = 80 + 567/280 = 647/280 - So, 20/70 + 81/40 = 647/280
In mixed form: 287/280
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