Add 21/30 and 18/56
21/30 + 18/56 is 143/140.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 56 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 30 × 28 = 840,
21/30 = 21 × 28/30 × 28 = 588/840 - Likewise, for the 2nd fraction, since 56 × 15 = 840,
18/56 = 18 × 15/56 × 15 = 270/840 - Add the two like fractions:
588/840 + 270/840 = 588 + 270/840 = 858/840 - 858/840 simplified gives 143/140
- So, 21/30 + 18/56 = 143/140
In mixed form: 13/140
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