Add 28/21 and 81/40
1st number: 1 7/21, 2nd number: 2 1/40
28/21 + 81/40 is 403/120.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 40 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 21 × 40 = 840,
28/21 = 28 × 40/21 × 40 = 1120/840 - Likewise, for the 2nd fraction, since 40 × 21 = 840,
81/40 = 81 × 21/40 × 21 = 1701/840 - Add the two like fractions:
1120/840 + 1701/840 = 1120 + 1701/840 = 2821/840 - 2821/840 simplified gives 403/120
- So, 28/21 + 81/40 = 403/120
In mixed form: 343/120
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