Add 21/30 and 42/54
21/30 + 42/54 is 133/90.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 54 is 270
Next, find the equivalent fraction of both fractional numbers with denominator 270 - For the 1st fraction, since 30 × 9 = 270,
21/30 = 21 × 9/30 × 9 = 189/270 - Likewise, for the 2nd fraction, since 54 × 5 = 270,
42/54 = 42 × 5/54 × 5 = 210/270 - Add the two like fractions:
189/270 + 210/270 = 189 + 210/270 = 399/270 - 399/270 simplified gives 133/90
- So, 21/30 + 42/54 = 133/90
In mixed form: 143/90
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