Subtract 21/15 from 18/98, Solve 18/98

Subtract 21/15 from 18/98

1^st number: 18/98, 2^nd number: 1 6/15

18/98 - 21/15 is -298/245.

Find the least common denominator or LCM of the two denominators:
LCM of 98 and 15 is 1470

Next, find the equivalent fraction of both fractional numbers with denominator 1470
For the 1st fraction, since 98 × 15 = 1470,
18/98 = 18 × 15/98 × 15 = 270/1470
Likewise, for the 2nd fraction, since 15 × 98 = 1470,
21/15 = 21 × 98/15 × 98 = 2058/1470
Subtract the two like fractions:
270/1470 - 2058/1470 = 270 - 2058/1470 = -1788/1470
After reducing the fraction, the answer is -298/245

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