Subtract 21/42 from 42/10, Solve 4 2/10

Subtract 21/42 from 42/10

1^st number: 4 2/10, 2^nd number: 21/42

42/10 - 21/42 is 37/10.

Find the least common denominator or LCM of the two denominators:
LCM of 10 and 42 is 210

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 10 × 21 = 210,
42/10 = 42 × 21/10 × 21 = 882/210
Likewise, for the 2nd fraction, since 42 × 5 = 210,
21/42 = 21 × 5/42 × 5 = 105/210
Subtract the two like fractions:
882/210 - 105/210 = 882 - 105/210 = 777/210
After reducing the fraction, the answer is 37/10
In mixed form: 37/10

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