Add 27/90 and 42/21
1st number: 27/90, 2nd number: 2 0/21
27/90 + 42/21 is 23/10.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 21 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 90 × 7 = 630,
27/90 = 27 × 7/90 × 7 = 189/630 - Likewise, for the 2nd fraction, since 21 × 30 = 630,
42/21 = 42 × 30/21 × 30 = 1260/630 - Add the two like fractions:
189/630 + 1260/630 = 189 + 1260/630 = 1449/630 - 1449/630 simplified gives 23/10
- So, 27/90 + 42/21 = 23/10
In mixed form: 23/10
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