Add 21/27 and 40/70
21/27 + 40/70 is 85/63.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 27 and 70 is 1890
Next, find the equivalent fraction of both fractional numbers with denominator 1890 - For the 1st fraction, since 27 × 70 = 1890,
21/27 = 21 × 70/27 × 70 = 1470/1890 - Likewise, for the 2nd fraction, since 70 × 27 = 1890,
40/70 = 40 × 27/70 × 27 = 1080/1890 - Add the two like fractions:
1470/1890 + 1080/1890 = 1470 + 1080/1890 = 2550/1890 - 2550/1890 simplified gives 85/63
- So, 21/27 + 40/70 = 85/63
In mixed form: 122/63
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