Add 21/42 and 45/20
1st number: 21/42, 2nd number: 2 5/20
21/42 + 45/20 is 11/4.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 20 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 42 × 10 = 420,
21/42 = 21 × 10/42 × 10 = 210/420 - Likewise, for the 2nd fraction, since 20 × 21 = 420,
45/20 = 45 × 21/20 × 21 = 945/420 - Add the two like fractions:
210/420 + 945/420 = 210 + 945/420 = 1155/420 - 1155/420 simplified gives 11/4
- So, 21/42 + 45/20 = 11/4
In mixed form: 23/4
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