Add 81/4 and 15/20
1st number: 20 1/4, 2nd number: 15/20
81/4 + 15/20 is 21/1.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 4 and 20 is 20
Next, find the equivalent fraction of both fractional numbers with denominator 20 - For the 1st fraction, since 4 × 5 = 20,
81/4 = 81 × 5/4 × 5 = 405/20 - Likewise, for the 2nd fraction, since 20 × 1 = 20,
15/20 = 15 × 1/20 × 1 = 15/20 - Add the two like fractions:
405/20 + 15/20 = 405 + 15/20 = 420/20 - 420/20 simplified gives 21/1
- So, 81/4 + 15/20 = 21/1
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