Add 72/18 and 90/20
1st number: 4 0/18, 2nd number: 4 10/20
72/18 + 90/20 is 17/2.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 20 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 18 × 10 = 180,
72/18 = 72 × 10/18 × 10 = 720/180 - Likewise, for the 2nd fraction, since 20 × 9 = 180,
90/20 = 90 × 9/20 × 9 = 810/180 - Add the two like fractions:
720/180 + 810/180 = 720 + 810/180 = 1530/180 - 1530/180 simplified gives 17/2
- So, 72/18 + 90/20 = 17/2
In mixed form: 81/2
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