Add 72/42 and 40/80
1st number: 1 30/42, 2nd number: 40/80
72/42 + 40/80 is 31/14.
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,
40/80 = 40 × 21/80 × 21 = 840/1680 - Add the two like fractions:
2880/1680 + 840/1680 = 2880 + 840/1680 = 3720/1680 - 3720/1680 simplified gives 31/14
- So, 72/42 + 40/80 = 31/14
In mixed form: 23/14
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