Add 20/12 and 42/45
1st number: 1 8/12, 2nd number: 42/45
20/12 + 42/45 is 13/5.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 45 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 12 × 15 = 180,
20/12 = 20 × 15/12 × 15 = 300/180 - Likewise, for the 2nd fraction, since 45 × 4 = 180,
42/45 = 42 × 4/45 × 4 = 168/180 - Add the two like fractions:
300/180 + 168/180 = 300 + 168/180 = 468/180 - 468/180 simplified gives 13/5
- So, 20/12 + 42/45 = 13/5
In mixed form: 23/5
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