Add 70/20 and 80/21
1st number: 3 10/20, 2nd number: 3 17/21
70/20 + 80/21 is 307/42.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 21 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 20 × 21 = 420,
70/20 = 70 × 21/20 × 21 = 1470/420 - Likewise, for the 2nd fraction, since 21 × 20 = 420,
80/21 = 80 × 20/21 × 20 = 1600/420 - Add the two like fractions:
1470/420 + 1600/420 = 1470 + 1600/420 = 3070/420 - 3070/420 simplified gives 307/42
- So, 70/20 + 80/21 = 307/42
In mixed form: 713/42
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