Add 21/70 and 42/54
21/70 + 42/54 is 97/90.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 54 is 1890
Next, find the equivalent fraction of both fractional numbers with denominator 1890 - For the 1st fraction, since 70 × 27 = 1890,
21/70 = 21 × 27/70 × 27 = 567/1890 - Likewise, for the 2nd fraction, since 54 × 35 = 1890,
42/54 = 42 × 35/54 × 35 = 1470/1890 - Add the two like fractions:
567/1890 + 1470/1890 = 567 + 1470/1890 = 2037/1890 - 2037/1890 simplified gives 97/90
- So, 21/70 + 42/54 = 97/90
In mixed form: 17/90
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