Add 45/72 and 8/21
45/72 + 8/21 is 169/168.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 21 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 72 × 7 = 504,
45/72 = 45 × 7/72 × 7 = 315/504 - Likewise, for the 2nd fraction, since 21 × 24 = 504,
8/21 = 8 × 24/21 × 24 = 192/504 - Add the two like fractions:
315/504 + 192/504 = 315 + 192/504 = 507/504 - 507/504 simplified gives 169/168
- So, 45/72 + 8/21 = 169/168
In mixed form: 11/168
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