Subtract 9/42 from 21/5, Solve 4 1/5

Subtract 9/42 from 21/5

1^st number: 4 1/5, 2^nd number: 9/42

21/5 - 9/42 is 279/70.

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,
9/42 = 9 × 5/42 × 5 = 45/210
Subtract the two like fractions:
882/210 - 45/210 = 882 - 45/210 = 837/210
After reducing the fraction, the answer is 279/70
In mixed form: 369/70

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