Add 3/21 and 21/72
3/21 + 21/72 is 73/168.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 72 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 21 × 24 = 504,
3/21 = 3 × 24/21 × 24 = 72/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
21/72 = 21 × 7/72 × 7 = 147/504 - Add the two like fractions:
72/504 + 147/504 = 72 + 147/504 = 219/504 - 219/504 simplified gives 73/168
- So, 3/21 + 21/72 = 73/168
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