Add 42/45 and 3/20
42/45 + 3/20 is 13/12.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 20 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 45 × 4 = 180,
42/45 = 42 × 4/45 × 4 = 168/180 - Likewise, for the 2nd fraction, since 20 × 9 = 180,
3/20 = 3 × 9/20 × 9 = 27/180 - Add the two like fractions:
168/180 + 27/180 = 168 + 27/180 = 195/180 - 195/180 simplified gives 13/12
- So, 42/45 + 3/20 = 13/12
In mixed form: 11/12
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