Add 72/42 and 20/80
1st number: 1 30/42, 2nd number: 20/80
72/42 + 20/80 is 55/28.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 80 is 1680
Next, find the equivalent fraction of both fractional numbers with denominator 1680 - For the 1st fraction, since 42 × 40 = 1680,
72/42 = 72 × 40/42 × 40 = 2880/1680 - Likewise, for the 2nd fraction, since 80 × 21 = 1680,
20/80 = 20 × 21/80 × 21 = 420/1680 - Add the two like fractions:
2880/1680 + 420/1680 = 2880 + 420/1680 = 3300/1680 - 3300/1680 simplified gives 55/28
- So, 72/42 + 20/80 = 55/28
In mixed form: 127/28
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