Add 80/84 and 70/21
1st number: 80/84, 2nd number: 3 7/21
80/84 + 70/21 is 30/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 21 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 84 × 1 = 84,
80/84 = 80 × 1/84 × 1 = 80/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
70/21 = 70 × 4/21 × 4 = 280/84 - Add the two like fractions:
80/84 + 280/84 = 80 + 280/84 = 360/84 - 360/84 simplified gives 30/7
- So, 80/84 + 70/21 = 30/7
In mixed form: 42/7
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