Add 1/21 and 20/45
1/21 + 20/45 is 31/63.
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,
1/21 = 1 × 15/21 × 15 = 15/315 - Likewise, for the 2nd fraction, since 45 × 7 = 315,
20/45 = 20 × 7/45 × 7 = 140/315 - Add the two like fractions:
15/315 + 140/315 = 15 + 140/315 = 155/315 - 155/315 simplified gives 31/63
- So, 1/21 + 20/45 = 31/63
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