Add 21/7 and 10/90
1st number: 3 0/7, 2nd number: 10/90
21/7 + 10/90 is 28/9.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 7 and 90 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 7 × 90 = 630,
21/7 = 21 × 90/7 × 90 = 1890/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
10/90 = 10 × 7/90 × 7 = 70/630 - Add the two like fractions:
1890/630 + 70/630 = 1890 + 70/630 = 1960/630 - 1960/630 simplified gives 28/9
- So, 21/7 + 10/90 = 28/9
In mixed form: 31/9
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