Add 21/54 and 42/70
21/54 + 42/70 is 89/90.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 54 and 70 is 1890
Next, find the equivalent fraction of both fractional numbers with denominator 1890 - For the 1st fraction, since 54 × 35 = 1890,
21/54 = 21 × 35/54 × 35 = 735/1890 - Likewise, for the 2nd fraction, since 70 × 27 = 1890,
42/70 = 42 × 27/70 × 27 = 1134/1890 - Add the two like fractions:
735/1890 + 1134/1890 = 735 + 1134/1890 = 1869/1890 - 1869/1890 simplified gives 89/90
- So, 21/54 + 42/70 = 89/90
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