Add 15/21 and 80/20
1st number: 15/21, 2nd number: 4 0/20
15/21 + 80/20 is 33/7.
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,
15/21 = 15 × 20/21 × 20 = 300/420 - Likewise, for the 2nd fraction, since 20 × 21 = 420,
80/20 = 80 × 21/20 × 21 = 1680/420 - Add the two like fractions:
300/420 + 1680/420 = 300 + 1680/420 = 1980/420 - 1980/420 simplified gives 33/7
- So, 15/21 + 80/20 = 33/7
In mixed form: 45/7
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