Subtract 21/14 from 42/10, Solve 4 2/10

Subtract 21/14 from 42/10

1^st number: 4 2/10, 2^nd number: 1 7/14

42/10 - 21/14 is 27/10.

Find the least common denominator or LCM of the two denominators:
LCM of 10 and 14 is 70

Next, find the equivalent fraction of both fractional numbers with denominator 70
For the 1st fraction, since 10 × 7 = 70,
42/10 = 42 × 7/10 × 7 = 294/70
Likewise, for the 2nd fraction, since 14 × 5 = 70,
21/14 = 21 × 5/14 × 5 = 105/70
Subtract the two like fractions:
294/70 - 105/70 = 294 - 105/70 = 189/70
After reducing the fraction, the answer is 27/10
In mixed form: 27/10

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