Add 70/80 and 9/42
70/80 + 9/42 is 61/56.
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,
70/80 = 70 × 21/80 × 21 = 1470/1680 - Likewise, for the 2nd fraction, since 42 × 40 = 1680,
9/42 = 9 × 40/42 × 40 = 360/1680 - Add the two like fractions:
1470/1680 + 360/1680 = 1470 + 360/1680 = 1830/1680 - 1830/1680 simplified gives 61/56
- So, 70/80 + 9/42 = 61/56
In mixed form: 15/56
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