Add 21/36 and 42/90
21/36 + 42/90 is 21/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 36 and 90 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 36 × 5 = 180,
21/36 = 21 × 5/36 × 5 = 105/180 - Likewise, for the 2nd fraction, since 90 × 2 = 180,
42/90 = 42 × 2/90 × 2 = 84/180 - Add the two like fractions:
105/180 + 84/180 = 105 + 84/180 = 189/180 - 189/180 simplified gives 21/20
- So, 21/36 + 42/90 = 21/20
In mixed form: 11/20
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