Add 21/40 and 42/54
21/40 + 42/54 is 469/360.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 54 is 1080
Next, find the equivalent fraction of both fractional numbers with denominator 1080 - For the 1st fraction, since 40 × 27 = 1080,
21/40 = 21 × 27/40 × 27 = 567/1080 - Likewise, for the 2nd fraction, since 54 × 20 = 1080,
42/54 = 42 × 20/54 × 20 = 840/1080 - Add the two like fractions:
567/1080 + 840/1080 = 567 + 840/1080 = 1407/1080 - 1407/1080 simplified gives 469/360
- So, 21/40 + 42/54 = 469/360
In mixed form: 1109/360
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