Add 21/40 and 8/15
21/40 + 8/15 is 127/120.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 15 is 120
Next, find the equivalent fraction of both fractional numbers with denominator 120 - For the 1st fraction, since 40 × 3 = 120,
21/40 = 21 × 3/40 × 3 = 63/120 - Likewise, for the 2nd fraction, since 15 × 8 = 120,
8/15 = 8 × 8/15 × 8 = 64/120 - Add the two like fractions:
63/120 + 64/120 = 63 + 64/120 = 127/120 - So, 21/40 + 8/15 = 127/120
In mixed form: 17/120
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