Add 20/45 and 84/21
1st number: 20/45, 2nd number: 4 0/21
20/45 + 84/21 is 40/9.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 21 is 315
Next, find the equivalent fraction of both fractional numbers with denominator 315 - For the 1st fraction, since 45 × 7 = 315,
20/45 = 20 × 7/45 × 7 = 140/315 - Likewise, for the 2nd fraction, since 21 × 15 = 315,
84/21 = 84 × 15/21 × 15 = 1260/315 - Add the two like fractions:
140/315 + 1260/315 = 140 + 1260/315 = 1400/315 - 1400/315 simplified gives 40/9
- So, 20/45 + 84/21 = 40/9
In mixed form: 44/9
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