Add 54/80 and 21/28
54/80 + 21/28 is 57/40.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 28 is 560
Next, find the equivalent fraction of both fractional numbers with denominator 560 - For the 1st fraction, since 80 × 7 = 560,
54/80 = 54 × 7/80 × 7 = 378/560 - Likewise, for the 2nd fraction, since 28 × 20 = 560,
21/28 = 21 × 20/28 × 20 = 420/560 - Add the two like fractions:
378/560 + 420/560 = 378 + 420/560 = 798/560 - 798/560 simplified gives 57/40
- So, 54/80 + 21/28 = 57/40
In mixed form: 117/40
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