Add 21/80 and 21/72
21/80 + 21/72 is 133/240.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 72 is 720
Next, find the equivalent fraction of both fractional numbers with denominator 720 - For the 1st fraction, since 80 × 9 = 720,
21/80 = 21 × 9/80 × 9 = 189/720 - Likewise, for the 2nd fraction, since 72 × 10 = 720,
21/72 = 21 × 10/72 × 10 = 210/720 - Add the two like fractions:
189/720 + 210/720 = 189 + 210/720 = 399/720 - 399/720 simplified gives 133/240
- So, 21/80 + 21/72 = 133/240
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