Add 21/72 and 18/28
21/72 + 18/28 is 157/168.
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,
18/28 = 18 × 18/28 × 18 = 324/504 - Add the two like fractions:
147/504 + 324/504 = 147 + 324/504 = 471/504 - 471/504 simplified gives 157/168
- So, 21/72 + 18/28 = 157/168
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