Add 21/45 and 12/90
21/45 + 12/90 is 3/5.
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,
21/45 = 21 × 2/45 × 2 = 42/90 - Likewise, for the 2nd fraction, since 90 × 1 = 90,
12/90 = 12 × 1/90 × 1 = 12/90 - Add the two like fractions:
42/90 + 12/90 = 42 + 12/90 = 54/90 - 54/90 simplified gives 3/5
- So, 21/45 + 12/90 = 3/5
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