Add 21/20 and 9/42
1st number: 1 1/20, 2nd number: 9/42
21/20 + 9/42 is 177/140.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 42 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 20 × 21 = 420,
21/20 = 21 × 21/20 × 21 = 441/420 - Likewise, for the 2nd fraction, since 42 × 10 = 420,
9/42 = 9 × 10/42 × 10 = 90/420 - Add the two like fractions:
441/420 + 90/420 = 441 + 90/420 = 531/420 - 531/420 simplified gives 177/140
- So, 21/20 + 9/42 = 177/140
In mixed form: 137/140
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