Add 21/60 and 80/90
21/60 + 80/90 is 223/180.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 60 and 90 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 60 × 3 = 180,
21/60 = 21 × 3/60 × 3 = 63/180 - Likewise, for the 2nd fraction, since 90 × 2 = 180,
80/90 = 80 × 2/90 × 2 = 160/180 - Add the two like fractions:
63/180 + 160/180 = 63 + 160/180 = 223/180 - So, 21/60 + 80/90 = 223/180
In mixed form: 143/180
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