Add 72/90 and 5/20
72/90 + 5/20 is 21/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 20 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 20 × 9 = 180,
5/20 = 5 × 9/20 × 9 = 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 + 5/20 = 21/20
In mixed form: 11/20
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