Add 5/20 and 21/42
5/20 + 21/42 is 3/4.
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,
5/20 = 5 × 21/20 × 21 = 105/420 - Likewise, for the 2nd fraction, since 42 × 10 = 420,
21/42 = 21 × 10/42 × 10 = 210/420 - Add the two like fractions:
105/420 + 210/420 = 105 + 210/420 = 315/420 - 315/420 simplified gives 3/4
- So, 5/20 + 21/42 = 3/4
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