Add 21/84 and 18/72
21/84 + 18/72 is 1/2.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 72 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 84 × 6 = 504,
21/84 = 21 × 6/84 × 6 = 126/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
18/72 = 18 × 7/72 × 7 = 126/504 - Add the two like fractions:
126/504 + 126/504 = 126 + 126/504 = 252/504 - 252/504 simplified gives 1/2
- So, 21/84 + 18/72 = 1/2
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