Add 45/72 and 20/42
45/72 + 20/42 is 185/168.
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,
45/72 = 45 × 7/72 × 7 = 315/504 - Likewise, for the 2nd fraction, since 42 × 12 = 504,
20/42 = 20 × 12/42 × 12 = 240/504 - Add the two like fractions:
315/504 + 240/504 = 315 + 240/504 = 555/504 - 555/504 simplified gives 185/168
- So, 45/72 + 20/42 = 185/168
In mixed form: 117/168
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