Add 20/45 and 21/42
20/45 + 21/42 is 17/18.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 42 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 45 × 14 = 630,
20/45 = 20 × 14/45 × 14 = 280/630 - Likewise, for the 2nd fraction, since 42 × 15 = 630,
21/42 = 21 × 15/42 × 15 = 315/630 - Add the two like fractions:
280/630 + 315/630 = 280 + 315/630 = 595/630 - 595/630 simplified gives 17/18
- So, 20/45 + 21/42 = 17/18
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