Add 21/15 and 90/20
1st number: 1 6/15, 2nd number: 4 10/20
21/15 + 90/20 is 59/10.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 20 is 60
Next, find the equivalent fraction of both fractional numbers with denominator 60 - For the 1st fraction, since 15 × 4 = 60,
21/15 = 21 × 4/15 × 4 = 84/60 - Likewise, for the 2nd fraction, since 20 × 3 = 60,
90/20 = 90 × 3/20 × 3 = 270/60 - Add the two like fractions:
84/60 + 270/60 = 84 + 270/60 = 354/60 - 354/60 simplified gives 59/10
- So, 21/15 + 90/20 = 59/10
In mixed form: 59/10
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