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