Subtract 98/40 from 80/84, Solve 80/84

Subtract 98/40 from 80/84

1^st number: 80/84, 2^nd number: 2 18/40

80/84 - 98/40 is -629/420.

Find the least common denominator or LCM of the two denominators:
LCM of 84 and 40 is 840

Next, find the equivalent fraction of both fractional numbers with denominator 840
For the 1st fraction, since 84 × 10 = 840,
80/84 = 80 × 10/84 × 10 = 800/840
Likewise, for the 2nd fraction, since 40 × 21 = 840,
98/40 = 98 × 21/40 × 21 = 2058/840
Subtract the two like fractions:
800/840 - 2058/840 = 800 - 2058/840 = -1258/840
After reducing the fraction, the answer is -629/420

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