Add 20/45 and 18/42
20/45 + 18/42 is 55/63.
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,
18/42 = 18 × 15/42 × 15 = 270/630 - Add the two like fractions:
280/630 + 270/630 = 280 + 270/630 = 550/630 - 550/630 simplified gives 55/63
- So, 20/45 + 18/42 = 55/63
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