Add 12/42 and 30/45
12/42 + 30/45 is 20/21.
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,
12/42 = 12 × 15/42 × 15 = 180/630 - Likewise, for the 2nd fraction, since 45 × 14 = 630,
30/45 = 30 × 14/45 × 14 = 420/630 - Add the two like fractions:
180/630 + 420/630 = 180 + 420/630 = 600/630 - 600/630 simplified gives 20/21
- So, 12/42 + 30/45 = 20/21
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