Add 18/21 and 10/20
18/21 + 10/20 is 19/14.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 20 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 21 × 20 = 420,
18/21 = 18 × 20/21 × 20 = 360/420 - Likewise, for the 2nd fraction, since 20 × 21 = 420,
10/20 = 10 × 21/20 × 21 = 210/420 - Add the two like fractions:
360/420 + 210/420 = 360 + 210/420 = 570/420 - 570/420 simplified gives 19/14
- So, 18/21 + 10/20 = 19/14
In mixed form: 15/14
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