Add 42/90 and 21/20
1st number: 42/90, 2nd number: 1 1/20
42/90 + 21/20 is 91/60.
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,
42/90 = 42 × 2/90 × 2 = 84/180 - Likewise, for the 2nd fraction, since 20 × 9 = 180,
21/20 = 21 × 9/20 × 9 = 189/180 - Add the two like fractions:
84/180 + 189/180 = 84 + 189/180 = 273/180 - 273/180 simplified gives 91/60
- So, 42/90 + 21/20 = 91/60
In mixed form: 131/60
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