Add 21/56 and 18/15
1st number: 21/56, 2nd number: 1 3/15
21/56 + 18/15 is 63/40.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 56 and 15 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 56 × 15 = 840,
21/56 = 21 × 15/56 × 15 = 315/840 - Likewise, for the 2nd fraction, since 15 × 56 = 840,
18/15 = 18 × 56/15 × 56 = 1008/840 - Add the two like fractions:
315/840 + 1008/840 = 315 + 1008/840 = 1323/840 - 1323/840 simplified gives 63/40
- So, 21/56 + 18/15 = 63/40
In mixed form: 123/40
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