Add 15/42 and 70/80
15/42 + 70/80 is 69/56.
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,
15/42 = 15 × 40/42 × 40 = 600/1680 - Likewise, for the 2nd fraction, since 80 × 21 = 1680,
70/80 = 70 × 21/80 × 21 = 1470/1680 - Add the two like fractions:
600/1680 + 1470/1680 = 600 + 1470/1680 = 2070/1680 - 2070/1680 simplified gives 69/56
- So, 15/42 + 70/80 = 69/56
In mixed form: 113/56
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