Add 3/20 and 21/42
3/20 + 21/42 is 13/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 42 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 20 × 21 = 420,
3/20 = 3 × 21/20 × 21 = 63/420 - Likewise, for the 2nd fraction, since 42 × 10 = 420,
21/42 = 21 × 10/42 × 10 = 210/420 - Add the two like fractions:
63/420 + 210/420 = 63 + 210/420 = 273/420 - 273/420 simplified gives 13/20
- So, 3/20 + 21/42 = 13/20
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