Add 21/70 and 35/28
1st number: 21/70, 2nd number: 1 7/28
21/70 + 35/28 is 31/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 28 is 140
Next, find the equivalent fraction of both fractional numbers with denominator 140 - For the 1st fraction, since 70 × 2 = 140,
21/70 = 21 × 2/70 × 2 = 42/140 - Likewise, for the 2nd fraction, since 28 × 5 = 140,
35/28 = 35 × 5/28 × 5 = 175/140 - Add the two like fractions:
42/140 + 175/140 = 42 + 175/140 = 217/140 - 217/140 simplified gives 31/20
- So, 21/70 + 35/28 = 31/20
In mixed form: 111/20
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