Add 15/20 and 21/30
15/20 + 21/30 is 29/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 30 is 60
Next, find the equivalent fraction of both fractional numbers with denominator 60 - For the 1st fraction, since 20 × 3 = 60,
15/20 = 15 × 3/20 × 3 = 45/60 - Likewise, for the 2nd fraction, since 30 × 2 = 60,
21/30 = 21 × 2/30 × 2 = 42/60 - Add the two like fractions:
45/60 + 42/60 = 45 + 42/60 = 87/60 - 87/60 simplified gives 29/20
- So, 15/20 + 21/30 = 29/20
In mixed form: 19/20
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