Add 21/7 and 54/90
1st number: 3 0/7, 2nd number: 54/90
21/7 + 54/90 is 18/5.
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,
54/90 = 54 × 7/90 × 7 = 378/630 - Add the two like fractions:
1890/630 + 378/630 = 1890 + 378/630 = 2268/630 - 2268/630 simplified gives 18/5
- So, 21/7 + 54/90 = 18/5
In mixed form: 33/5
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