Add 21/72 and 18/42
21/72 + 18/42 is 121/168.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 42 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 42 × 12 = 504,
18/42 = 18 × 12/42 × 12 = 216/504 - Add the two like fractions:
147/504 + 216/504 = 147 + 216/504 = 363/504 - 363/504 simplified gives 121/168
- So, 21/72 + 18/42 = 121/168
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