Add 20/21 and 70/80
20/21 + 70/80 is 307/168.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 80 is 1680
Next, find the equivalent fraction of both fractional numbers with denominator 1680 - For the 1st fraction, since 21 × 80 = 1680,
20/21 = 20 × 80/21 × 80 = 1600/1680 - Likewise, for the 2nd fraction, since 80 × 21 = 1680,
70/80 = 70 × 21/80 × 21 = 1470/1680 - Add the two like fractions:
1600/1680 + 1470/1680 = 1600 + 1470/1680 = 3070/1680 - 3070/1680 simplified gives 307/168
- So, 20/21 + 70/80 = 307/168
In mixed form: 1139/168
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