Subtract 12/42 from 21/5, Solve 4 1/5

Subtract 12/42 from 21/5

1^st number: 4 1/5, 2^nd number: 12/42

21/5 - 12/42 is 137/35.

Find the least common denominator or LCM of the two denominators:
LCM of 5 and 42 is 210

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 5 × 42 = 210,
21/5 = 21 × 42/5 × 42 = 882/210
Likewise, for the 2nd fraction, since 42 × 5 = 210,
12/42 = 12 × 5/42 × 5 = 60/210
Subtract the two like fractions:
882/210 - 60/210 = 882 - 60/210 = 822/210
After reducing the fraction, the answer is 137/35
In mixed form: 332/35

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