Add 28/21 and 20/45
1st number: 1 7/21, 2nd number: 20/45
28/21 + 20/45 is 16/9.
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,
28/21 = 28 × 15/21 × 15 = 420/315 - Likewise, for the 2nd fraction, since 45 × 7 = 315,
20/45 = 20 × 7/45 × 7 = 140/315 - Add the two like fractions:
420/315 + 140/315 = 420 + 140/315 = 560/315 - 560/315 simplified gives 16/9
- So, 28/21 + 20/45 = 16/9
In mixed form: 17/9
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