Add 21/45 and 42/54
21/45 + 42/54 is 56/45.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 54 is 270
Next, find the equivalent fraction of both fractional numbers with denominator 270 - For the 1st fraction, since 45 × 6 = 270,
21/45 = 21 × 6/45 × 6 = 126/270 - Likewise, for the 2nd fraction, since 54 × 5 = 270,
42/54 = 42 × 5/54 × 5 = 210/270 - Add the two like fractions:
126/270 + 210/270 = 126 + 210/270 = 336/270 - 336/270 simplified gives 56/45
- So, 21/45 + 42/54 = 56/45
In mixed form: 111/45
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