Add 80/42 and 70/40
1st number: 1 38/42, 2nd number: 1 30/40
80/42 + 70/40 is 307/84.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 40 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 42 × 20 = 840,
80/42 = 80 × 20/42 × 20 = 1600/840 - Likewise, for the 2nd fraction, since 40 × 21 = 840,
70/40 = 70 × 21/40 × 21 = 1470/840 - Add the two like fractions:
1600/840 + 1470/840 = 1600 + 1470/840 = 3070/840 - 3070/840 simplified gives 307/84
- So, 80/42 + 70/40 = 307/84
In mixed form: 355/84
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