Add 72/20 and 90/40
1st number: 3 12/20, 2nd number: 2 10/40
72/20 + 90/40 is 117/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 40 is 40
Next, find the equivalent fraction of both fractional numbers with denominator 40 - For the 1st fraction, since 20 × 2 = 40,
72/20 = 72 × 2/20 × 2 = 144/40 - Likewise, for the 2nd fraction, since 40 × 1 = 40,
90/40 = 90 × 1/40 × 1 = 90/40 - Add the two like fractions:
144/40 + 90/40 = 144 + 90/40 = 234/40 - 234/40 simplified gives 117/20
- So, 72/20 + 90/40 = 117/20
In mixed form: 517/20
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