Add 21/28 and 20/70
21/28 + 20/70 is 29/28.
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,
20/70 = 20 × 2/70 × 2 = 40/140 - Add the two like fractions:
105/140 + 40/140 = 105 + 40/140 = 145/140 - 145/140 simplified gives 29/28
- So, 21/28 + 20/70 = 29/28
In mixed form: 11/28
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