Add 21/15 and 12/40
1st number: 1 6/15, 2nd number: 12/40
21/15 + 12/40 is 17/10.
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,
12/40 = 12 × 3/40 × 3 = 36/120 - Add the two like fractions:
168/120 + 36/120 = 168 + 36/120 = 204/120 - 204/120 simplified gives 17/10
- So, 21/15 + 12/40 = 17/10
In mixed form: 17/10
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