Add 12/21 and 20/15
1st number: 12/21, 2nd number: 1 5/15
12/21 + 20/15 is 40/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 15 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 21 × 5 = 105,
12/21 = 12 × 5/21 × 5 = 60/105 - Likewise, for the 2nd fraction, since 15 × 7 = 105,
20/15 = 20 × 7/15 × 7 = 140/105 - Add the two like fractions:
60/105 + 140/105 = 60 + 140/105 = 200/105 - 200/105 simplified gives 40/21
- So, 12/21 + 20/15 = 40/21
In mixed form: 119/21
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