Add 21/54 and 42/90
21/54 + 42/90 is 77/90.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 54 and 90 is 270
Next, find the equivalent fraction of both fractional numbers with denominator 270 - For the 1st fraction, since 54 × 5 = 270,
21/54 = 21 × 5/54 × 5 = 105/270 - Likewise, for the 2nd fraction, since 90 × 3 = 270,
42/90 = 42 × 3/90 × 3 = 126/270 - Add the two like fractions:
105/270 + 126/270 = 105 + 126/270 = 231/270 - 231/270 simplified gives 77/90
- So, 21/54 + 42/90 = 77/90
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