Add 42/72 and 72/80
42/72 + 72/80 is 89/60.
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,
42/72 = 42 × 10/72 × 10 = 420/720 - Likewise, for the 2nd fraction, since 80 × 9 = 720,
72/80 = 72 × 9/80 × 9 = 648/720 - Add the two like fractions:
420/720 + 648/720 = 420 + 648/720 = 1068/720 - 1068/720 simplified gives 89/60
- So, 42/72 + 72/80 = 89/60
In mixed form: 129/60
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