Add 30/21 and 90/72
1st number: 1 9/21, 2nd number: 1 18/72
30/21 + 90/72 is 75/28.
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,
30/21 = 30 × 24/21 × 24 = 720/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
90/72 = 90 × 7/72 × 7 = 630/504 - Add the two like fractions:
720/504 + 630/504 = 720 + 630/504 = 1350/504 - 1350/504 simplified gives 75/28
- So, 30/21 + 90/72 = 75/28
In mixed form: 219/28
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