Add 72/21 and 90/7
1st number: 3 9/21, 2nd number: 12 6/7
72/21 + 90/7 is 114/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 7 is 21
Next, find the equivalent fraction of both fractional numbers with denominator 21 - For the 1st fraction, since 21 × 1 = 21,
72/21 = 72 × 1/21 × 1 = 72/21 - Likewise, for the 2nd fraction, since 7 × 3 = 21,
90/7 = 90 × 3/7 × 3 = 270/21 - Add the two like fractions:
72/21 + 270/21 = 72 + 270/21 = 342/21 - 342/21 simplified gives 114/7
- So, 72/21 + 90/7 = 114/7
In mixed form: 162/7
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