Add 21/8 and 20/40
1st number: 2 5/8, 2nd number: 20/40
21/8 + 20/40 is 25/8.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 40 is 40
Next, find the equivalent fraction of both fractional numbers with denominator 40 - For the 1st fraction, since 8 × 5 = 40,
21/8 = 21 × 5/8 × 5 = 105/40 - Likewise, for the 2nd fraction, since 40 × 1 = 40,
20/40 = 20 × 1/40 × 1 = 20/40 - Add the two like fractions:
105/40 + 20/40 = 105 + 20/40 = 125/40 - 125/40 simplified gives 25/8
- So, 21/8 + 20/40 = 25/8
In mixed form: 31/8
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