Add 15/56 and 21/40
15/56 + 21/40 is 111/140.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 56 and 40 is 280
Next, find the equivalent fraction of both fractional numbers with denominator 280 - For the 1st fraction, since 56 × 5 = 280,
15/56 = 15 × 5/56 × 5 = 75/280 - Likewise, for the 2nd fraction, since 40 × 7 = 280,
21/40 = 21 × 7/40 × 7 = 147/280 - Add the two like fractions:
75/280 + 147/280 = 75 + 147/280 = 222/280 - 222/280 simplified gives 111/140
- So, 15/56 + 21/40 = 111/140
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