Add 21/40 and 18/15
1st number: 21/40, 2nd number: 1 3/15
21/40 + 18/15 is 69/40.
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,
18/15 = 18 × 8/15 × 8 = 144/120 - Add the two like fractions:
63/120 + 144/120 = 63 + 144/120 = 207/120 - 207/120 simplified gives 69/40
- So, 21/40 + 18/15 = 69/40
In mixed form: 129/40
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