Add 21/40 and 8/5
1st number: 21/40, 2nd number: 1 3/5
21/40 + 8/5 is 17/8.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 5 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 5 × 8 = 40,
8/5 = 8 × 8/5 × 8 = 64/40 - Add the two like fractions:
21/40 + 64/40 = 21 + 64/40 = 85/40 - 85/40 simplified gives 17/8
- So, 21/40 + 8/5 = 17/8
In mixed form: 21/8
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