Add 15/28 and 30/72
15/28 + 30/72 is 20/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 72 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 28 × 18 = 504,
15/28 = 15 × 18/28 × 18 = 270/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
30/72 = 30 × 7/72 × 7 = 210/504 - Add the two like fractions:
270/504 + 210/504 = 270 + 210/504 = 480/504 - 480/504 simplified gives 20/21
- So, 15/28 + 30/72 = 20/21
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