Add 21/42 and 25/45
21/42 + 25/45 is 19/18.
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,
21/42 = 21 × 15/42 × 15 = 315/630 - Likewise, for the 2nd fraction, since 45 × 14 = 630,
25/45 = 25 × 14/45 × 14 = 350/630 - Add the two like fractions:
315/630 + 350/630 = 315 + 350/630 = 665/630 - 665/630 simplified gives 19/18
- So, 21/42 + 25/45 = 19/18
In mixed form: 11/18
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