Add 21/90 and 42/20
1st number: 21/90, 2nd number: 2 2/20
21/90 + 42/20 is 7/3.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 20 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 90 × 2 = 180,
21/90 = 21 × 2/90 × 2 = 42/180 - Likewise, for the 2nd fraction, since 20 × 9 = 180,
42/20 = 42 × 9/20 × 9 = 378/180 - Add the two like fractions:
42/180 + 378/180 = 42 + 378/180 = 420/180 - 420/180 simplified gives 7/3
- So, 21/90 + 42/20 = 7/3
In mixed form: 21/3
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