Subtract 3/40 from 21/6, Solve 3 3/6

Subtract 3/40 from 21/6

1^st number: 3 3/6, 2^nd number: 3/40

21/6 - 3/40 is 137/40.

Find the least common denominator or LCM of the two denominators:
LCM of 6 and 40 is 120

Next, find the equivalent fraction of both fractional numbers with denominator 120
For the 1st fraction, since 6 × 20 = 120,
21/6 = 21 × 20/6 × 20 = 420/120
Likewise, for the 2nd fraction, since 40 × 3 = 120,
3/40 = 3 × 3/40 × 3 = 9/120
Subtract the two like fractions:
420/120 - 9/120 = 420 - 9/120 = 411/120
After reducing the fraction, the answer is 137/40
In mixed form: 317/40

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