Add 21/15 and 42/20
1st number: 1 6/15, 2nd number: 2 2/20
21/15 + 42/20 is 7/2.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 20 is 60
Next, find the equivalent fraction of both fractional numbers with denominator 60 - For the 1st fraction, since 15 × 4 = 60,
21/15 = 21 × 4/15 × 4 = 84/60 - Likewise, for the 2nd fraction, since 20 × 3 = 60,
42/20 = 42 × 3/20 × 3 = 126/60 - Add the two like fractions:
84/60 + 126/60 = 84 + 126/60 = 210/60 - 210/60 simplified gives 7/2
- So, 21/15 + 42/20 = 7/2
In mixed form: 31/2
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