Add 21/28 and 42/70
21/28 + 42/70 is 27/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 70 is 140
Next, find the equivalent fraction of both fractional numbers with denominator 140 - For the 1st fraction, since 28 × 5 = 140,
21/28 = 21 × 5/28 × 5 = 105/140 - Likewise, for the 2nd fraction, since 70 × 2 = 140,
42/70 = 42 × 2/70 × 2 = 84/140 - Add the two like fractions:
105/140 + 84/140 = 105 + 84/140 = 189/140 - 189/140 simplified gives 27/20
- So, 21/28 + 42/70 = 27/20
In mixed form: 17/20
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