Add 72/90 and 45/12
1st number: 72/90, 2nd number: 3 9/12
72/90 + 45/12 is 91/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 12 is 180 - For the 1st fraction, since 90 × 2 = 180,
72/90 = 72 × 2/90 × 2 = 144/180 - Likewise, for the 2nd fraction, since 12 × 15 = 180,
45/12 = 45 × 15/12 × 15 = 675/180 - Add the two fractions:
144/180 + 675/180 = 144 + 675/180 = 819/180 - 819/180 simplified gives 91/20
- So, 72/90 + 45/12 = 91/20
In mixed form: 411/20
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