Add 18/21 and 20/45
18/21 + 20/45 is 82/63.
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,
18/21 = 18 × 15/21 × 15 = 270/315 - Likewise, for the 2nd fraction, since 45 × 7 = 315,
20/45 = 20 × 7/45 × 7 = 140/315 - Add the two like fractions:
270/315 + 140/315 = 270 + 140/315 = 410/315 - 410/315 simplified gives 82/63
- So, 18/21 + 20/45 = 82/63
In mixed form: 119/63
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