Add 72/20 and 90/7
1st number: 3 12/20, 2nd number: 12 6/7
72/20 + 90/7 is 576/35.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 7 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 7 × 20 = 140,
90/7 = 90 × 20/7 × 20 = 1800/140 - Add the two like fractions:
504/140 + 1800/140 = 504 + 1800/140 = 2304/140 - 2304/140 simplified gives 576/35
- So, 72/20 + 90/7 = 576/35
In mixed form: 1616/35
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