Add 15/45 and 21/90
15/45 + 21/90 is 17/30.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 90 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 45 × 2 = 90,
15/45 = 15 × 2/45 × 2 = 30/90 - Likewise, for the 2nd fraction, since 90 × 1 = 90,
21/90 = 21 × 1/90 × 1 = 21/90 - Add the two like fractions:
30/90 + 21/90 = 30 + 21/90 = 51/90 - 51/90 simplified gives 17/30
- So, 15/45 + 21/90 = 17/30
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