Add 9/10 and 21/40
9/10 + 21/40 is 57/40.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 10 and 40 is 40
Next, find the equivalent fraction of both fractional numbers with denominator 40 - For the 1st fraction, since 10 × 4 = 40,
9/10 = 9 × 4/10 × 4 = 36/40 - Likewise, for the 2nd fraction, since 40 × 1 = 40,
21/40 = 21 × 1/40 × 1 = 21/40 - Add the two like fractions:
36/40 + 21/40 = 36 + 21/40 = 57/40 - So, 9/10 + 21/40 = 57/40
In mixed form: 117/40
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