Add 28/21 and 40/72
1st number: 1 7/21, 2nd number: 40/72
28/21 + 40/72 is 17/9.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 72 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 21 × 24 = 504,
28/21 = 28 × 24/21 × 24 = 672/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
40/72 = 40 × 7/72 × 7 = 280/504 - Add the two like fractions:
672/504 + 280/504 = 672 + 280/504 = 952/504 - 952/504 simplified gives 17/9
- So, 28/21 + 40/72 = 17/9
In mixed form: 18/9
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