Add 72/84 and 30/80
72/84 + 30/80 is 69/56.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 80 is 1680
Next, find the equivalent fraction of both fractional numbers with denominator 1680 - For the 1st fraction, since 84 × 20 = 1680,
72/84 = 72 × 20/84 × 20 = 1440/1680 - Likewise, for the 2nd fraction, since 80 × 21 = 1680,
30/80 = 30 × 21/80 × 21 = 630/1680 - Add the two like fractions:
1440/1680 + 630/1680 = 1440 + 630/1680 = 2070/1680 - 2070/1680 simplified gives 69/56
- So, 72/84 + 30/80 = 69/56
In mixed form: 113/56
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