Add 21/35 and 40/90
21/35 + 40/90 is 47/45.
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,
21/35 = 21 × 18/35 × 18 = 378/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
40/90 = 40 × 7/90 × 7 = 280/630 - Add the two like fractions:
378/630 + 280/630 = 378 + 280/630 = 658/630 - 658/630 simplified gives 47/45
- So, 21/35 + 40/90 = 47/45
In mixed form: 12/45
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