Add 20/21 and 18/35
20/21 + 18/35 is 22/15.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 35 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 21 × 5 = 105,
20/21 = 20 × 5/21 × 5 = 100/105 - Likewise, for the 2nd fraction, since 35 × 3 = 105,
18/35 = 18 × 3/35 × 3 = 54/105 - Add the two like fractions:
100/105 + 54/105 = 100 + 54/105 = 154/105 - 154/105 simplified gives 22/15
- So, 20/21 + 18/35 = 22/15
In mixed form: 17/15
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