Add 20/42 and 70/80
20/42 + 70/80 is 227/168.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 80 is 1680
Next, find the equivalent fraction of both fractional numbers with denominator 1680 - For the 1st fraction, since 42 × 40 = 1680,
20/42 = 20 × 40/42 × 40 = 800/1680 - Likewise, for the 2nd fraction, since 80 × 21 = 1680,
70/80 = 70 × 21/80 × 21 = 1470/1680 - Add the two like fractions:
800/1680 + 1470/1680 = 800 + 1470/1680 = 2270/1680 - 2270/1680 simplified gives 227/168
- So, 20/42 + 70/80 = 227/168
In mixed form: 159/168
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