Add 21/40 and 63/56
1st number: 21/40, 2nd number: 1 7/56
21/40 + 63/56 is 33/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 56 is 280
Next, find the equivalent fraction of both fractional numbers with denominator 280 - For the 1st fraction, since 40 × 7 = 280,
21/40 = 21 × 7/40 × 7 = 147/280 - Likewise, for the 2nd fraction, since 56 × 5 = 280,
63/56 = 63 × 5/56 × 5 = 315/280 - Add the two like fractions:
147/280 + 315/280 = 147 + 315/280 = 462/280 - 462/280 simplified gives 33/20
- So, 21/40 + 63/56 = 33/20
In mixed form: 113/20
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