Subtract 15/42 from 70/80
70/80 - 15/42 is 29/56.
Steps for subtracting 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,
15/42 = 15 × 40/42 × 40 = 600/1680 - Subtract the two like fractions:
1470/1680 - 600/1680 = 1470 - 600/1680 = 870/1680 - After reducing the fraction, the answer is 29/56
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