Add 20/42 and 30/90
20/42 + 30/90 is 17/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 90 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 90 × 7 = 630,
30/90 = 30 × 7/90 × 7 = 210/630 - Add the two like fractions:
300/630 + 210/630 = 300 + 210/630 = 510/630 - 510/630 simplified gives 17/21
- So, 20/42 + 30/90 = 17/21
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