Add 21/40 and 15/16
21/40 + 15/16 is 117/80.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 16 is 80
Next, find the equivalent fraction of both fractional numbers with denominator 80 - For the 1st fraction, since 40 × 2 = 80,
21/40 = 21 × 2/40 × 2 = 42/80 - Likewise, for the 2nd fraction, since 16 × 5 = 80,
15/16 = 15 × 5/16 × 5 = 75/80 - Add the two like fractions:
42/80 + 75/80 = 42 + 75/80 = 117/80 - So, 21/40 + 15/16 = 117/80
In mixed form: 137/80
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