Add 21/56 and 9/15
21/56 + 9/15 is 39/40.
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,
9/15 = 9 × 56/15 × 56 = 504/840 - Add the two like fractions:
315/840 + 504/840 = 315 + 504/840 = 819/840 - 819/840 simplified gives 39/40
- So, 21/56 + 9/15 = 39/40
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