Add 72/20 and 42/45
1st number: 3 12/20, 2nd number: 42/45
72/20 + 42/45 is 68/15.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 45 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 20 × 9 = 180,
72/20 = 72 × 9/20 × 9 = 648/180 - Likewise, for the 2nd fraction, since 45 × 4 = 180,
42/45 = 42 × 4/45 × 4 = 168/180 - Add the two like fractions:
648/180 + 168/180 = 648 + 168/180 = 816/180 - 816/180 simplified gives 68/15
- So, 72/20 + 42/45 = 68/15
In mixed form: 48/15
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