Subtract 42/98 from 21/30, Solve 21/30

Subtract 42/98 from 21/30

21/30 - 42/98 is 19/70.

Find the least common denominator or LCM of the two denominators:
LCM of 30 and 98 is 1470

Next, find the equivalent fraction of both fractional numbers with denominator 1470
For the 1st fraction, since 30 × 49 = 1470,
21/30 = 21 × 49/30 × 49 = 1029/1470
Likewise, for the 2nd fraction, since 98 × 15 = 1470,
42/98 = 42 × 15/98 × 15 = 630/1470
Subtract the two like fractions:
1029/1470 - 630/1470 = 1029 - 630/1470 = 399/1470
After reducing the fraction, the answer is 19/70

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