Add 21/84 and 45/20
1st number: 21/84, 2nd number: 2 5/20
21/84 + 45/20 is 5/2.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 20 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 84 × 5 = 420,
21/84 = 21 × 5/84 × 5 = 105/420 - Likewise, for the 2nd fraction, since 20 × 21 = 420,
45/20 = 45 × 21/20 × 21 = 945/420 - Add the two like fractions:
105/420 + 945/420 = 105 + 945/420 = 1050/420 - 1050/420 simplified gives 5/2
- So, 21/84 + 45/20 = 5/2
In mixed form: 21/2
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