Add 18/3 and 90/21
1st number: 6 0/3, 2nd number: 4 6/21
18/3 + 90/21 is 72/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 3 and 21 is 21
Next, find the equivalent fraction of both fractional numbers with denominator 21 - For the 1st fraction, since 3 × 7 = 21,
18/3 = 18 × 7/3 × 7 = 126/21 - Likewise, for the 2nd fraction, since 21 × 1 = 21,
90/21 = 90 × 1/21 × 1 = 90/21 - Add the two like fractions:
126/21 + 90/21 = 126 + 90/21 = 216/21 - 216/21 simplified gives 72/7
- So, 18/3 + 90/21 = 72/7
In mixed form: 102/7
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