Add 21/15 and 20/90
1st number: 1 6/15, 2nd number: 20/90
21/15 + 20/90 is 73/45.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 90 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 15 × 6 = 90,
21/15 = 21 × 6/15 × 6 = 126/90 - Likewise, for the 2nd fraction, since 90 × 1 = 90,
20/90 = 20 × 1/90 × 1 = 20/90 - Add the two like fractions:
126/90 + 20/90 = 126 + 20/90 = 146/90 - 146/90 simplified gives 73/45
- So, 21/15 + 20/90 = 73/45
In mixed form: 128/45
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