Add 28/42 and 42/90
28/42 + 42/90 is 17/15.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 90 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 42 × 15 = 630,
28/42 = 28 × 15/42 × 15 = 420/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
42/90 = 42 × 7/90 × 7 = 294/630 - Add the two like fractions:
420/630 + 294/630 = 420 + 294/630 = 714/630 - 714/630 simplified gives 17/15
- So, 28/42 + 42/90 = 17/15
In mixed form: 12/15
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