Add 21/7 and 18/90
1st number: 3 0/7, 2nd number: 18/90
21/7 + 18/90 is 16/5.
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,
18/90 = 18 × 7/90 × 7 = 126/630 - Add the two like fractions:
1890/630 + 126/630 = 1890 + 126/630 = 2016/630 - 2016/630 simplified gives 16/5
- So, 21/7 + 18/90 = 16/5
In mixed form: 31/5
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