Subtract 21/6 from 42/5, Solve 8 2/5

Subtract 21/6 from 42/5

1^st number: 8 2/5, 2^nd number: 3 3/6

42/5 - 21/6 is 49/10.

Find the least common denominator or LCM of the two denominators:
LCM of 5 and 6 is 30

Next, find the equivalent fraction of both fractional numbers with denominator 30
For the 1st fraction, since 5 × 6 = 30,
42/5 = 42 × 6/5 × 6 = 252/30
Likewise, for the 2nd fraction, since 6 × 5 = 30,
21/6 = 21 × 5/6 × 5 = 105/30
Subtract the two like fractions:
252/30 - 105/30 = 252 - 105/30 = 147/30
After reducing the fraction, the answer is 49/10
In mixed form: 49/10

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