Add 21/40 and 5/8
21/40 + 5/8 is 23/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 8 is 40
Next, find the equivalent fraction of both fractional numbers with denominator 40 - For the 1st fraction, since 40 × 1 = 40,
21/40 = 21 × 1/40 × 1 = 21/40 - Likewise, for the 2nd fraction, since 8 × 5 = 40,
5/8 = 5 × 5/8 × 5 = 25/40 - Add the two like fractions:
21/40 + 25/40 = 21 + 25/40 = 46/40 - 46/40 simplified gives 23/20
- So, 21/40 + 5/8 = 23/20
In mixed form: 13/20
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