Subtract 10/49 from 21/30, Solve 21/30

Subtract 10/49 from 21/30

21/30 - 10/49 is 243/490.

Find the least common denominator or LCM of the two denominators:
LCM of 30 and 49 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 49 × 30 = 1470,
10/49 = 10 × 30/49 × 30 = 300/1470
Subtract the two like fractions:
1029/1470 - 300/1470 = 1029 - 300/1470 = 729/1470
After reducing the fraction, the answer is 243/490

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