Subtract 18/80 from 98/70, Solve 1 28/70

Subtract 18/80 from 98/70

1^st number: 1 28/70, 2^nd number: 18/80

98/70 - 18/80 is 47/40.

Find the least common denominator or LCM of the two denominators:
LCM of 70 and 80 is 560

Next, find the equivalent fraction of both fractional numbers with denominator 560
For the 1st fraction, since 70 × 8 = 560,
98/70 = 98 × 8/70 × 8 = 784/560
Likewise, for the 2nd fraction, since 80 × 7 = 560,
18/80 = 18 × 7/80 × 7 = 126/560
Subtract the two like fractions:
784/560 - 126/560 = 784 - 126/560 = 658/560
After reducing the fraction, the answer is 47/40
In mixed form: 17/40

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