Add 30/72 and 80/21
1st number: 30/72, 2nd number: 3 17/21
30/72 + 80/21 is 355/84.
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,
30/72 = 30 × 7/72 × 7 = 210/504 - Likewise, for the 2nd fraction, since 21 × 24 = 504,
80/21 = 80 × 24/21 × 24 = 1920/504 - Add the two like fractions:
210/504 + 1920/504 = 210 + 1920/504 = 2130/504 - 2130/504 simplified gives 355/84
- So, 30/72 + 80/21 = 355/84
In mixed form: 419/84
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