Add 21/30 and 72/9
1st number: 21/30, 2nd number: 8 0/9
21/30 + 72/9 is 87/10.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 9 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 30 × 3 = 90,
21/30 = 21 × 3/30 × 3 = 63/90 - Likewise, for the 2nd fraction, since 9 × 10 = 90,
72/9 = 72 × 10/9 × 10 = 720/90 - Add the two like fractions:
63/90 + 720/90 = 63 + 720/90 = 783/90 - 783/90 simplified gives 87/10
- So, 21/30 + 72/9 = 87/10
In mixed form: 87/10
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