Add 72/21 and 90/30
1st number: 3 9/21, 2nd number: 3 0/30
72/21 + 90/30 is 45/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 30 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 21 × 10 = 210,
72/21 = 72 × 10/21 × 10 = 720/210 - Likewise, for the 2nd fraction, since 30 × 7 = 210,
90/30 = 90 × 7/30 × 7 = 630/210 - Add the two like fractions:
720/210 + 630/210 = 720 + 630/210 = 1350/210 - 1350/210 simplified gives 45/7
- So, 72/21 + 90/30 = 45/7
In mixed form: 63/7
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