Add 15/20 and 21/56
15/20 + 21/56 is 9/8.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 56 is 280
Next, find the equivalent fraction of both fractional numbers with denominator 280 - For the 1st fraction, since 20 × 14 = 280,
15/20 = 15 × 14/20 × 14 = 210/280 - Likewise, for the 2nd fraction, since 56 × 5 = 280,
21/56 = 21 × 5/56 × 5 = 105/280 - Add the two like fractions:
210/280 + 105/280 = 210 + 105/280 = 315/280 - 315/280 simplified gives 9/8
- So, 15/20 + 21/56 = 9/8
In mixed form: 11/8
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