Add 20/21 and 2/5
20/21 + 2/5 is 142/105.
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,
20/21 = 20 × 5/21 × 5 = 100/105 - Likewise, for the 2nd fraction, since 5 × 21 = 105,
2/5 = 2 × 21/5 × 21 = 42/105 - Add the two like fractions:
100/105 + 42/105 = 100 + 42/105 = 142/105 - So, 20/21 + 2/5 = 142/105
In mixed form: 137/105
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