Add 72/20 and 90/28
1st number: 3 12/20, 2nd number: 3 6/28
72/20 + 90/28 is 477/70.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 28 is 140
Next, find the equivalent fraction of both fractional numbers with denominator 140 - For the 1st fraction, since 20 × 7 = 140,
72/20 = 72 × 7/20 × 7 = 504/140 - Likewise, for the 2nd fraction, since 28 × 5 = 140,
90/28 = 90 × 5/28 × 5 = 450/140 - Add the two like fractions:
504/140 + 450/140 = 504 + 450/140 = 954/140 - 954/140 simplified gives 477/70
- So, 72/20 + 90/28 = 477/70
In mixed form: 657/70
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