Add 80/42 and 21/72
1st number: 1 38/42, 2nd number: 21/72
80/42 + 21/72 is 123/56.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 72 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 42 × 12 = 504,
80/42 = 80 × 12/42 × 12 = 960/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
21/72 = 21 × 7/72 × 7 = 147/504 - Add the two like fractions:
960/504 + 147/504 = 960 + 147/504 = 1107/504 - 1107/504 simplified gives 123/56
- So, 80/42 + 21/72 = 123/56
In mixed form: 211/56
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