Add 20/21 and 49/45
1st number: 20/21, 2nd number: 1 4/45
20/21 + 49/45 is 643/315.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 45 is 315
Next, find the equivalent fraction of both fractional numbers with denominator 315 - For the 1st fraction, since 21 × 15 = 315,
20/21 = 20 × 15/21 × 15 = 300/315 - Likewise, for the 2nd fraction, since 45 × 7 = 315,
49/45 = 49 × 7/45 × 7 = 343/315 - Add the two like fractions:
300/315 + 343/315 = 300 + 343/315 = 643/315 - So, 20/21 + 49/45 = 643/315
In mixed form: 213/315
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