Add 54/56 and 21/40
54/56 + 21/40 is 417/280.
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,
54/56 = 54 × 5/56 × 5 = 270/280 - Likewise, for the 2nd fraction, since 40 × 7 = 280,
21/40 = 21 × 7/40 × 7 = 147/280 - Add the two like fractions:
270/280 + 147/280 = 270 + 147/280 = 417/280 - So, 54/56 + 21/40 = 417/280
In mixed form: 1137/280
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