Add 28/21 and 12/80
1st number: 1 7/21, 2nd number: 12/80
28/21 + 12/80 is 89/60.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 80 is 1680
Next, find the equivalent fraction of both fractional numbers with denominator 1680 - For the 1st fraction, since 21 × 80 = 1680,
28/21 = 28 × 80/21 × 80 = 2240/1680 - Likewise, for the 2nd fraction, since 80 × 21 = 1680,
12/80 = 12 × 21/80 × 21 = 252/1680 - Add the two like fractions:
2240/1680 + 252/1680 = 2240 + 252/1680 = 2492/1680 - 2492/1680 simplified gives 89/60
- So, 28/21 + 12/80 = 89/60
In mixed form: 129/60
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