Add 42/45 and 21/54
42/45 + 21/54 is 119/90.
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,
42/45 = 42 × 6/45 × 6 = 252/270 - Likewise, for the 2nd fraction, since 54 × 5 = 270,
21/54 = 21 × 5/54 × 5 = 105/270 - Add the two like fractions:
252/270 + 105/270 = 252 + 105/270 = 357/270 - 357/270 simplified gives 119/90
- So, 42/45 + 21/54 = 119/90
In mixed form: 129/90
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