Add 72/80 and 28/21
1st number: 72/80, 2nd number: 1 7/21
72/80 + 28/21 is 67/30.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 21 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 21 × 80 = 1680,
28/21 = 28 × 80/21 × 80 = 2240/1680 - Add the two like fractions:
1512/1680 + 2240/1680 = 1512 + 2240/1680 = 3752/1680 - 3752/1680 simplified gives 67/30
- So, 72/80 + 28/21 = 67/30
In mixed form: 27/30
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