Add 15/20 and 90/70
1st number: 15/20, 2nd number: 1 20/70
15/20 + 90/70 is 57/28.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 70 is 140
Next, find the equivalent fraction of both fractional numbers with denominator 140 - For the 1st fraction, since 20 × 7 = 140,
15/20 = 15 × 7/20 × 7 = 105/140 - Likewise, for the 2nd fraction, since 70 × 2 = 140,
90/70 = 90 × 2/70 × 2 = 180/140 - Add the two like fractions:
105/140 + 180/140 = 105 + 180/140 = 285/140 - 285/140 simplified gives 57/28
- So, 15/20 + 90/70 = 57/28
In mixed form: 21/28
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