Add 72/80 and 21/56
72/80 + 21/56 is 51/40.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 56 is 560
Next, find the equivalent fraction of both fractional numbers with denominator 560 - For the 1st fraction, since 80 × 7 = 560,
72/80 = 72 × 7/80 × 7 = 504/560 - Likewise, for the 2nd fraction, since 56 × 10 = 560,
21/56 = 21 × 10/56 × 10 = 210/560 - Add the two like fractions:
504/560 + 210/560 = 504 + 210/560 = 714/560 - 714/560 simplified gives 51/40
- So, 72/80 + 21/56 = 51/40
In mixed form: 111/40
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