Add 21/70 and 70/9
1st number: 21/70, 2nd number: 7 7/9
21/70 + 70/9 is 727/90.
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,
70/9 = 70 × 70/9 × 70 = 4900/630 - Add the two like fractions:
189/630 + 4900/630 = 189 + 4900/630 = 5089/630 - 5089/630 simplified gives 727/90
- So, 21/70 + 70/9 = 727/90
In mixed form: 87/90
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