Add 21/45 and 28/42
21/45 + 28/42 is 17/15.
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,
28/42 = 28 × 15/42 × 15 = 420/630 - Add the two like fractions:
294/630 + 420/630 = 294 + 420/630 = 714/630 - 714/630 simplified gives 17/15
- So, 21/45 + 28/42 = 17/15
In mixed form: 12/15
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