Add 40/42 and 21/27
40/42 + 21/27 is 109/63.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 27 is 378
Next, find the equivalent fraction of both fractional numbers with denominator 378 - For the 1st fraction, since 42 × 9 = 378,
40/42 = 40 × 9/42 × 9 = 360/378 - Likewise, for the 2nd fraction, since 27 × 14 = 378,
21/27 = 21 × 14/27 × 14 = 294/378 - Add the two like fractions:
360/378 + 294/378 = 360 + 294/378 = 654/378 - 654/378 simplified gives 109/63
- So, 40/42 + 21/27 = 109/63
In mixed form: 146/63
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