Add 70/21 and 80/42
1st number: 3 7/21, 2nd number: 1 38/42
70/21 + 80/42 is 110/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 42 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 21 × 2 = 42,
70/21 = 70 × 2/21 × 2 = 140/42 - Likewise, for the 2nd fraction, since 42 × 1 = 42,
80/42 = 80 × 1/42 × 1 = 80/42 - Add the two like fractions:
140/42 + 80/42 = 140 + 80/42 = 220/42 - 220/42 simplified gives 110/21
- So, 70/21 + 80/42 = 110/21
In mixed form: 55/21
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