Add 20/42 and 21/45
20/42 + 21/45 is 33/35.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 45 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 42 × 15 = 630,
20/42 = 20 × 15/42 × 15 = 300/630 - Likewise, for the 2nd fraction, since 45 × 14 = 630,
21/45 = 21 × 14/45 × 14 = 294/630 - Add the two like fractions:
300/630 + 294/630 = 300 + 294/630 = 594/630 - 594/630 simplified gives 33/35
- So, 20/42 + 21/45 = 33/35
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