Add 20/72 and 21/80
20/72 + 21/80 is 389/720.
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,
20/72 = 20 × 10/72 × 10 = 200/720 - Likewise, for the 2nd fraction, since 80 × 9 = 720,
21/80 = 21 × 9/80 × 9 = 189/720 - Add the two like fractions:
200/720 + 189/720 = 200 + 189/720 = 389/720 - So, 20/72 + 21/80 = 389/720
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