Add 15/40 and 21/20
1st number: 15/40, 2nd number: 1 1/20
15/40 + 21/20 is 57/40.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 20 is 40
Next, find the equivalent fraction of both fractional numbers with denominator 40 - For the 1st fraction, since 40 × 1 = 40,
15/40 = 15 × 1/40 × 1 = 15/40 - Likewise, for the 2nd fraction, since 20 × 2 = 40,
21/20 = 21 × 2/20 × 2 = 42/40 - Add the two like fractions:
15/40 + 42/40 = 15 + 42/40 = 57/40 - So, 15/40 + 21/20 = 57/40
In mixed form: 117/40
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