Add 21/70 and 28/9
1st number: 21/70, 2nd number: 3 1/9
21/70 + 28/9 is 307/90.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 9 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 70 × 9 = 630,
21/70 = 21 × 9/70 × 9 = 189/630 - Likewise, for the 2nd fraction, since 9 × 70 = 630,
28/9 = 28 × 70/9 × 70 = 1960/630 - Add the two like fractions:
189/630 + 1960/630 = 189 + 1960/630 = 2149/630 - 2149/630 simplified gives 307/90
- So, 21/70 + 28/9 = 307/90
In mixed form: 337/90
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