Add 2/5 and 3/21
2/5 + 3/21 is 19/35.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 5 and 21 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 5 × 21 = 105,
2/5 = 2 × 21/5 × 21 = 42/105 - Likewise, for the 2nd fraction, since 21 × 5 = 105,
3/21 = 3 × 5/21 × 5 = 15/105 - Add the two like fractions:
42/105 + 15/105 = 42 + 15/105 = 57/105 - 57/105 simplified gives 19/35
- So, 2/5 + 3/21 = 19/35
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