Add 21/28 and 20/5
1st number: 21/28, 2nd number: 4 0/5
21/28 + 20/5 is 19/4.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 5 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 5 × 28 = 140,
20/5 = 20 × 28/5 × 28 = 560/140 - Add the two like fractions:
105/140 + 560/140 = 105 + 560/140 = 665/140 - 665/140 simplified gives 19/4
- So, 21/28 + 20/5 = 19/4
In mixed form: 43/4
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