Add 12/21 and 90/18
1st number: 12/21, 2nd number: 5 0/18
12/21 + 90/18 is 39/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 18 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 21 × 6 = 126,
12/21 = 12 × 6/21 × 6 = 72/126 - Likewise, for the 2nd fraction, since 18 × 7 = 126,
90/18 = 90 × 7/18 × 7 = 630/126 - Add the two like fractions:
72/126 + 630/126 = 72 + 630/126 = 702/126 - 702/126 simplified gives 39/7
- So, 12/21 + 90/18 = 39/7
In mixed form: 54/7
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