Add 21/72 and 9/28
21/72 + 9/28 is 103/168.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 28 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 72 × 7 = 504,
21/72 = 21 × 7/72 × 7 = 147/504 - Likewise, for the 2nd fraction, since 28 × 18 = 504,
9/28 = 9 × 18/28 × 18 = 162/504 - Add the two like fractions:
147/504 + 162/504 = 147 + 162/504 = 309/504 - 309/504 simplified gives 103/168
- So, 21/72 + 9/28 = 103/168
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