Add 21/36 and 15/30
21/36 + 15/30 is 13/12.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 36 and 30 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 36 × 5 = 180,
21/36 = 21 × 5/36 × 5 = 105/180 - Likewise, for the 2nd fraction, since 30 × 6 = 180,
15/30 = 15 × 6/30 × 6 = 90/180 - Add the two like fractions:
105/180 + 90/180 = 105 + 90/180 = 195/180 - 195/180 simplified gives 13/12
- So, 21/36 + 15/30 = 13/12
In mixed form: 11/12
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