Add 21/40 and 28/49
21/40 + 28/49 is 307/280.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 49 is 1960
Next, find the equivalent fraction of both fractional numbers with denominator 1960 - For the 1st fraction, since 40 × 49 = 1960,
21/40 = 21 × 49/40 × 49 = 1029/1960 - Likewise, for the 2nd fraction, since 49 × 40 = 1960,
28/49 = 28 × 40/49 × 40 = 1120/1960 - Add the two like fractions:
1029/1960 + 1120/1960 = 1029 + 1120/1960 = 2149/1960 - 2149/1960 simplified gives 307/280
- So, 21/40 + 28/49 = 307/280
In mixed form: 127/280
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