Add 21/18 and 21/20
1st number: 1 3/18, 2nd number: 1 1/20
21/18 + 21/20 is 133/60.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 20 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 18 × 10 = 180,
21/18 = 21 × 10/18 × 10 = 210/180 - Likewise, for the 2nd fraction, since 20 × 9 = 180,
21/20 = 21 × 9/20 × 9 = 189/180 - Add the two like fractions:
210/180 + 189/180 = 210 + 189/180 = 399/180 - 399/180 simplified gives 133/60
- So, 21/18 + 21/20 = 133/60
In mixed form: 213/60
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