Add 21/35 and 18/21
21/35 + 18/21 is 51/35.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 35 and 21 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 35 × 3 = 105,
21/35 = 21 × 3/35 × 3 = 63/105 - Likewise, for the 2nd fraction, since 21 × 5 = 105,
18/21 = 18 × 5/21 × 5 = 90/105 - Add the two like fractions:
63/105 + 90/105 = 63 + 90/105 = 153/105 - 153/105 simplified gives 51/35
- So, 21/35 + 18/21 = 51/35
In mixed form: 116/35
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