Subtract 42/10 from 2/21, Solve 2/21

Subtract 42/10 from 2/21

1^st number: 2/21, 2^nd number: 4 2/10

2/21 - 42/10 is -431/105.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 10 is 210

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 21 × 10 = 210,
2/21 = 2 × 10/21 × 10 = 20/210
Likewise, for the 2nd fraction, since 10 × 21 = 210,
42/10 = 42 × 21/10 × 21 = 882/210
Subtract the two like fractions:
20/210 - 882/210 = 20 - 882/210 = -862/210
After reducing the fraction, the answer is -431/105

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