Add 9/20 and 3/21
9/20 + 3/21 is 83/140.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 21 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 20 × 21 = 420,
9/20 = 9 × 21/20 × 21 = 189/420 - Likewise, for the 2nd fraction, since 21 × 20 = 420,
3/21 = 3 × 20/21 × 20 = 60/420 - Add the two like fractions:
189/420 + 60/420 = 189 + 60/420 = 249/420 - 249/420 simplified gives 83/140
- So, 9/20 + 3/21 = 83/140
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