Add 80/42 and 90/70
1st number: 1 38/42, 2nd number: 1 20/70
80/42 + 90/70 is 67/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 70 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 42 × 5 = 210,
80/42 = 80 × 5/42 × 5 = 400/210 - Likewise, for the 2nd fraction, since 70 × 3 = 210,
90/70 = 90 × 3/70 × 3 = 270/210 - Add the two like fractions:
400/210 + 270/210 = 400 + 270/210 = 670/210 - 670/210 simplified gives 67/21
- So, 80/42 + 90/70 = 67/21
In mixed form: 34/21
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