Add 45/80 and 20/42
45/80 + 20/42 is 349/336.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 42 is 1680
Next, find the equivalent fraction of both fractional numbers with denominator 1680 - For the 1st fraction, since 80 × 21 = 1680,
45/80 = 45 × 21/80 × 21 = 945/1680 - Likewise, for the 2nd fraction, since 42 × 40 = 1680,
20/42 = 20 × 40/42 × 40 = 800/1680 - Add the two like fractions:
945/1680 + 800/1680 = 945 + 800/1680 = 1745/1680 - 1745/1680 simplified gives 349/336
- So, 45/80 + 20/42 = 349/336
In mixed form: 113/336
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