Add 28/42 and 40/72
28/42 + 40/72 is 11/9.
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,
28/42 = 28 × 12/42 × 12 = 336/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
40/72 = 40 × 7/72 × 7 = 280/504 - Add the two like fractions:
336/504 + 280/504 = 336 + 280/504 = 616/504 - 616/504 simplified gives 11/9
- So, 28/42 + 40/72 = 11/9
In mixed form: 12/9
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