Add 15/72 and 30/21
1st number: 15/72, 2nd number: 1 9/21
15/72 + 30/21 is 275/168.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 21 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 72 × 7 = 504,
15/72 = 15 × 7/72 × 7 = 105/504 - Likewise, for the 2nd fraction, since 21 × 24 = 504,
30/21 = 30 × 24/21 × 24 = 720/504 - Add the two like fractions:
105/504 + 720/504 = 105 + 720/504 = 825/504 - 825/504 simplified gives 275/168
- So, 15/72 + 30/21 = 275/168
In mixed form: 1107/168
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