Add 15/5 and 12/21
1st number: 3 0/5, 2nd number: 12/21
15/5 + 12/21 is 25/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 5 and 21 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 5 × 21 = 105,
15/5 = 15 × 21/5 × 21 = 315/105 - Likewise, for the 2nd fraction, since 21 × 5 = 105,
12/21 = 12 × 5/21 × 5 = 60/105 - Add the two like fractions:
315/105 + 60/105 = 315 + 60/105 = 375/105 - 375/105 simplified gives 25/7
- So, 15/5 + 12/21 = 25/7
In mixed form: 34/7
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