Add 21/72 and 4/7
21/72 + 4/7 is 145/168.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 7 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 7 × 72 = 504,
4/7 = 4 × 72/7 × 72 = 288/504 - Add the two like fractions:
147/504 + 288/504 = 147 + 288/504 = 435/504 - 435/504 simplified gives 145/168
- So, 21/72 + 4/7 = 145/168
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