Add 72/45 and 45/20
1st number: 1 27/45, 2nd number: 2 5/20
72/45 + 45/20 is 77/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 20 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 45 × 4 = 180,
72/45 = 72 × 4/45 × 4 = 288/180 - Likewise, for the 2nd fraction, since 20 × 9 = 180,
45/20 = 45 × 9/20 × 9 = 405/180 - Add the two like fractions:
288/180 + 405/180 = 288 + 405/180 = 693/180 - 693/180 simplified gives 77/20
- So, 72/45 + 45/20 = 77/20
In mixed form: 317/20
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