Add 21/72 and 42/15
1st number: 21/72, 2nd number: 2 12/15
21/72 + 42/15 is 371/120.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 15 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 72 × 5 = 360,
21/72 = 21 × 5/72 × 5 = 105/360 - Likewise, for the 2nd fraction, since 15 × 24 = 360,
42/15 = 42 × 24/15 × 24 = 1008/360 - Add the two like fractions:
105/360 + 1008/360 = 105 + 1008/360 = 1113/360 - 1113/360 simplified gives 371/120
- So, 21/72 + 42/15 = 371/120
In mixed form: 311/120
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