Add 9/21 and 9/20
9/21 + 9/20 is 123/140.
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,
9/21 = 9 × 20/21 × 20 = 180/420 - Likewise, for the 2nd fraction, since 20 × 21 = 420,
9/20 = 9 × 21/20 × 21 = 189/420 - Add the two like fractions:
180/420 + 189/420 = 180 + 189/420 = 369/420 - 369/420 simplified gives 123/140
- So, 9/21 + 9/20 = 123/140
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