Add 21/18 and 90/72
1st number: 1 3/18, 2nd number: 1 18/72
21/18 + 90/72 is 29/12.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 72 is 72
Next, find the equivalent fraction of both fractional numbers with denominator 72 - For the 1st fraction, since 18 × 4 = 72,
21/18 = 21 × 4/18 × 4 = 84/72 - Likewise, for the 2nd fraction, since 72 × 1 = 72,
90/72 = 90 × 1/72 × 1 = 90/72 - Add the two like fractions:
84/72 + 90/72 = 84 + 90/72 = 174/72 - 174/72 simplified gives 29/12
- So, 21/18 + 90/72 = 29/12
In mixed form: 25/12
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