Subtract 3/10 from 21/56, Solve 21/56

Subtract 3/10 from 21/56

21/56 - 3/10 is 3/40.

Find the least common denominator or LCM of the two denominators:
LCM of 56 and 10 is 280

Next, find the equivalent fraction of both fractional numbers with denominator 280
For the 1st fraction, since 56 × 5 = 280,
21/56 = 21 × 5/56 × 5 = 105/280
Likewise, for the 2nd fraction, since 10 × 28 = 280,
3/10 = 3 × 28/10 × 28 = 84/280
Subtract the two like fractions:
105/280 - 84/280 = 105 - 84/280 = 21/280
After reducing the fraction, the answer is 3/40

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