Add 21/15 and 28/40
1st number: 1 6/15, 2nd number: 28/40
21/15 + 28/40 is 21/10.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 40 is 120
Next, find the equivalent fraction of both fractional numbers with denominator 120 - For the 1st fraction, since 15 × 8 = 120,
21/15 = 21 × 8/15 × 8 = 168/120 - Likewise, for the 2nd fraction, since 40 × 3 = 120,
28/40 = 28 × 3/40 × 3 = 84/120 - Add the two like fractions:
168/120 + 84/120 = 168 + 84/120 = 252/120 - 252/120 simplified gives 21/10
- So, 21/15 + 28/40 = 21/10
In mixed form: 21/10
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