Add 7/8 and 21/20
1st number: 7/8, 2nd number: 1 1/20
7/8 + 21/20 is 77/40.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 20 is 40
Next, find the equivalent fraction of both fractional numbers with denominator 40 - For the 1st fraction, since 8 × 5 = 40,
7/8 = 7 × 5/8 × 5 = 35/40 - Likewise, for the 2nd fraction, since 20 × 2 = 40,
21/20 = 21 × 2/20 × 2 = 42/40 - Add the two like fractions:
35/40 + 42/40 = 35 + 42/40 = 77/40 - So, 7/8 + 21/20 = 77/40
In mixed form: 137/40
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