Add 54/72 and 21/80
54/72 + 21/80 is 81/80.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 80 is 720
Next, find the equivalent fraction of both fractional numbers with denominator 720 - For the 1st fraction, since 72 × 10 = 720,
54/72 = 54 × 10/72 × 10 = 540/720 - Likewise, for the 2nd fraction, since 80 × 9 = 720,
21/80 = 21 × 9/80 × 9 = 189/720 - Add the two like fractions:
540/720 + 189/720 = 540 + 189/720 = 729/720 - 729/720 simplified gives 81/80
- So, 54/72 + 21/80 = 81/80
In mixed form: 11/80
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