Add 3/4 and 21/40
3/4 + 21/40 is 51/40.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 4 and 40 is 40
Next, find the equivalent fraction of both fractional numbers with denominator 40 - For the 1st fraction, since 4 × 10 = 40,
3/4 = 3 × 10/4 × 10 = 30/40 - Likewise, for the 2nd fraction, since 40 × 1 = 40,
21/40 = 21 × 1/40 × 1 = 21/40 - Add the two like fractions:
30/40 + 21/40 = 30 + 21/40 = 51/40 - So, 3/4 + 21/40 = 51/40
In mixed form: 111/40
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