Add 72/90 and 3/12
72/90 + 3/12 is 21/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 12 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 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,
3/12 = 3 × 15/12 × 15 = 45/180 - Add the two like fractions:
144/180 + 45/180 = 144 + 45/180 = 189/180 - 189/180 simplified gives 21/20
- So, 72/90 + 3/12 = 21/20
In mixed form: 11/20
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