Add 72/80 and 28/42
72/80 + 28/42 is 47/30.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 42 is 1680
Next, find the equivalent fraction of both fractional numbers with denominator 1680 - For the 1st fraction, since 80 × 21 = 1680,
72/80 = 72 × 21/80 × 21 = 1512/1680 - Likewise, for the 2nd fraction, since 42 × 40 = 1680,
28/42 = 28 × 40/42 × 40 = 1120/1680 - Add the two like fractions:
1512/1680 + 1120/1680 = 1512 + 1120/1680 = 2632/1680 - 2632/1680 simplified gives 47/30
- So, 72/80 + 28/42 = 47/30
In mixed form: 117/30
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