Add 9/20 and 72/21
1st number: 9/20, 2nd number: 3 9/21
9/20 + 72/21 is 543/140.
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,
72/21 = 72 × 20/21 × 20 = 1440/420 - Add the two like fractions:
189/420 + 1440/420 = 189 + 1440/420 = 1629/420 - 1629/420 simplified gives 543/140
- So, 9/20 + 72/21 = 543/140
In mixed form: 3123/140
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