Add 72/20 and 21/80
1st number: 3 12/20, 2nd number: 21/80
72/20 + 21/80 is 309/80.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 80 is 80
Next, find the equivalent fraction of both fractional numbers with denominator 80 - For the 1st fraction, since 20 × 4 = 80,
72/20 = 72 × 4/20 × 4 = 288/80 - Likewise, for the 2nd fraction, since 80 × 1 = 80,
21/80 = 21 × 1/80 × 1 = 21/80 - Add the two like fractions:
288/80 + 21/80 = 288 + 21/80 = 309/80 - So, 72/20 + 21/80 = 309/80
In mixed form: 369/80
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