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