Add 21/42 and 12/45
21/42 + 12/45 is 23/30.
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,
12/45 = 12 × 14/45 × 14 = 168/630 - Add the two like fractions:
315/630 + 168/630 = 315 + 168/630 = 483/630 - 483/630 simplified gives 23/30
- So, 21/42 + 12/45 = 23/30
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