Add 18/80 and 63/21
1st number: 18/80, 2nd number: 3 0/21
18/80 + 63/21 is 129/40.
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,
18/80 = 18 × 21/80 × 21 = 378/1680 - Likewise, for the 2nd fraction, since 21 × 80 = 1680,
63/21 = 63 × 80/21 × 80 = 5040/1680 - Add the two like fractions:
378/1680 + 5040/1680 = 378 + 5040/1680 = 5418/1680 - 5418/1680 simplified gives 129/40
- So, 18/80 + 63/21 = 129/40
In mixed form: 39/40
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