Add 21/15 and 84/40
1st number: 1 6/15, 2nd number: 2 4/40
21/15 + 84/40 is 7/2.
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,
84/40 = 84 × 3/40 × 3 = 252/120 - Add the two like fractions:
168/120 + 252/120 = 168 + 252/120 = 420/120 - 420/120 simplified gives 7/2
- So, 21/15 + 84/40 = 7/2
In mixed form: 31/2
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