Add 21/49 and 81/40
1st number: 21/49, 2nd number: 2 1/40
21/49 + 81/40 is 687/280.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 49 and 40 is 1960
Next, find the equivalent fraction of both fractional numbers with denominator 1960 - For the 1st fraction, since 49 × 40 = 1960,
21/49 = 21 × 40/49 × 40 = 840/1960 - Likewise, for the 2nd fraction, since 40 × 49 = 1960,
81/40 = 81 × 49/40 × 49 = 3969/1960 - Add the two like fractions:
840/1960 + 3969/1960 = 840 + 3969/1960 = 4809/1960 - 4809/1960 simplified gives 687/280
- So, 21/49 + 81/40 = 687/280
In mixed form: 2127/280
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