Add 21/90 and 42/54
21/90 + 42/54 is 91/90.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 54 is 270
Next, find the equivalent fraction of both fractional numbers with denominator 270 - For the 1st fraction, since 90 × 3 = 270,
21/90 = 21 × 3/90 × 3 = 63/270 - Likewise, for the 2nd fraction, since 54 × 5 = 270,
42/54 = 42 × 5/54 × 5 = 210/270 - Add the two like fractions:
63/270 + 210/270 = 63 + 210/270 = 273/270 - 273/270 simplified gives 91/90
- So, 21/90 + 42/54 = 91/90
In mixed form: 11/90
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