Add 21/35 and 20/21
21/35 + 20/21 is 163/105.
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,
20/21 = 20 × 5/21 × 5 = 100/105 - Add the two like fractions:
63/105 + 100/105 = 63 + 100/105 = 163/105 - So, 21/35 + 20/21 = 163/105
In mixed form: 158/105
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