Add 28/35 and 21/90
28/35 + 21/90 is 31/30.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 35 and 90 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 35 × 18 = 630,
28/35 = 28 × 18/35 × 18 = 504/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
21/90 = 21 × 7/90 × 7 = 147/630 - Add the two like fractions:
504/630 + 147/630 = 504 + 147/630 = 651/630 - 651/630 simplified gives 31/30
- So, 28/35 + 21/90 = 31/30
In mixed form: 11/30
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