Add 21/30 and 15/45
21/30 + 15/45 is 31/30.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 45 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 30 × 3 = 90,
21/30 = 21 × 3/30 × 3 = 63/90 - Likewise, for the 2nd fraction, since 45 × 2 = 90,
15/45 = 15 × 2/45 × 2 = 30/90 - Add the two like fractions:
63/90 + 30/90 = 63 + 30/90 = 93/90 - 93/90 simplified gives 31/30
- So, 21/30 + 15/45 = 31/30
In mixed form: 11/30
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