Add 18/42 and 30/45
18/42 + 30/45 is 23/21.
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,
18/42 = 18 × 15/42 × 15 = 270/630 - Likewise, for the 2nd fraction, since 45 × 14 = 630,
30/45 = 30 × 14/45 × 14 = 420/630 - Add the two like fractions:
270/630 + 420/630 = 270 + 420/630 = 690/630 - 690/630 simplified gives 23/21
- So, 18/42 + 30/45 = 23/21
In mixed form: 12/21
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