Add 20/21 and 15/35
20/21 + 15/35 is 29/21.
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,
15/35 = 15 × 3/35 × 3 = 45/105 - Add the two like fractions:
100/105 + 45/105 = 100 + 45/105 = 145/105 - 145/105 simplified gives 29/21
- So, 20/21 + 15/35 = 29/21
In mixed form: 18/21
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