Add 4/21 and 45/72
4/21 + 45/72 is 137/168.
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,
4/21 = 4 × 24/21 × 24 = 96/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
45/72 = 45 × 7/72 × 7 = 315/504 - Add the two like fractions:
96/504 + 315/504 = 96 + 315/504 = 411/504 - 411/504 simplified gives 137/168
- So, 4/21 + 45/72 = 137/168
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