Add 4/21 and 12/20
4/21 + 12/20 is 83/105.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 20 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 21 × 20 = 420,
4/21 = 4 × 20/21 × 20 = 80/420 - Likewise, for the 2nd fraction, since 20 × 21 = 420,
12/20 = 12 × 21/20 × 21 = 252/420 - Add the two like fractions:
80/420 + 252/420 = 80 + 252/420 = 332/420 - 332/420 simplified gives 83/105
- So, 4/21 + 12/20 = 83/105
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