Add 3/5 and 21/40
3/5 + 21/40 is 9/8.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 5 and 40 is 40
Next, find the equivalent fraction of both fractional numbers with denominator 40 - For the 1st fraction, since 5 × 8 = 40,
3/5 = 3 × 8/5 × 8 = 24/40 - Likewise, for the 2nd fraction, since 40 × 1 = 40,
21/40 = 21 × 1/40 × 1 = 21/40 - Add the two like fractions:
24/40 + 21/40 = 24 + 21/40 = 45/40 - 45/40 simplified gives 9/8
- So, 3/5 + 21/40 = 9/8
In mixed form: 11/8
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