Add 21/45 and 12/42
21/45 + 12/42 is 79/105.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 42 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 45 × 14 = 630,
21/45 = 21 × 14/45 × 14 = 294/630 - Likewise, for the 2nd fraction, since 42 × 15 = 630,
12/42 = 12 × 15/42 × 15 = 180/630 - Add the two like fractions:
294/630 + 180/630 = 294 + 180/630 = 474/630 - 474/630 simplified gives 79/105
- So, 21/45 + 12/42 = 79/105
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