Add 21/40 and 27/21
1st number: 21/40, 2nd number: 1 6/21
21/40 + 27/21 is 507/280.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 21 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 40 × 21 = 840,
21/40 = 21 × 21/40 × 21 = 441/840 - Likewise, for the 2nd fraction, since 21 × 40 = 840,
27/21 = 27 × 40/21 × 40 = 1080/840 - Add the two like fractions:
441/840 + 1080/840 = 441 + 1080/840 = 1521/840 - 1521/840 simplified gives 507/280
- So, 21/40 + 27/21 = 507/280
In mixed form: 1227/280
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