Add 42/80 and 18/72
42/80 + 18/72 is 31/40.
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,
42/80 = 42 × 9/80 × 9 = 378/720 - Likewise, for the 2nd fraction, since 72 × 10 = 720,
18/72 = 18 × 10/72 × 10 = 180/720 - Add the two like fractions:
378/720 + 180/720 = 378 + 180/720 = 558/720 - 558/720 simplified gives 31/40
- So, 42/80 + 18/72 = 31/40
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