Subtract 98/80 from 21/42
1st number: 21/42, 2nd number: 1 18/80
21/42 - 98/80 is -29/40.
Steps for subtracting 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,
21/42 = 21 × 40/42 × 40 = 840/1680 - Likewise, for the 2nd fraction, since 80 × 21 = 1680,
98/80 = 98 × 21/80 × 21 = 2058/1680 - Subtract the two like fractions:
840/1680 - 2058/1680 = 840 - 2058/1680 = -1218/1680 - After reducing the fraction, the answer is -29/40
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