Add 18/21 and 54/84
18/21 + 54/84 is 3/2.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 84 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 21 × 4 = 84,
18/21 = 18 × 4/21 × 4 = 72/84 - Likewise, for the 2nd fraction, since 84 × 1 = 84,
54/84 = 54 × 1/84 × 1 = 54/84 - Add the two like fractions:
72/84 + 54/84 = 72 + 54/84 = 126/84 - 126/84 simplified gives 3/2
- So, 18/21 + 54/84 = 3/2
In mixed form: 11/2
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