Add 12/21 and 45/20
1st number: 12/21, 2nd number: 2 5/20
12/21 + 45/20 is 79/28.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 20 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 21 × 20 = 420,
12/21 = 12 × 20/21 × 20 = 240/420 - Likewise, for the 2nd fraction, since 20 × 21 = 420,
45/20 = 45 × 21/20 × 21 = 945/420 - Add the two like fractions:
240/420 + 945/420 = 240 + 945/420 = 1185/420 - 1185/420 simplified gives 79/28
- So, 12/21 + 45/20 = 79/28
In mixed form: 223/28
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