Add 21/15 and 90/9
1st number: 1 6/15, 2nd number: 10 0/9
21/15 + 90/9 is 57/5.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 9 is 45
Next, find the equivalent fraction of both fractional numbers with denominator 45 - For the 1st fraction, since 15 × 3 = 45,
21/15 = 21 × 3/15 × 3 = 63/45 - Likewise, for the 2nd fraction, since 9 × 5 = 45,
90/9 = 90 × 5/9 × 5 = 450/45 - Add the two like fractions:
63/45 + 450/45 = 63 + 450/45 = 513/45 - 513/45 simplified gives 57/5
- So, 21/15 + 90/9 = 57/5
In mixed form: 112/5
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