Subtract 18/40 from 21/5, Solve 4 1/5

Subtract 18/40 from 21/5

1^st number: 4 1/5, 2^nd number: 18/40

21/5 - 18/40 is 15/4.

Find the least common denominator or LCM of the two denominators:
LCM of 5 and 40 is 40

Next, find the equivalent fraction of both fractional numbers with denominator 40
For the 1st fraction, since 5 × 8 = 40,
21/5 = 21 × 8/5 × 8 = 168/40
Likewise, for the 2nd fraction, since 40 × 1 = 40,
18/40 = 18 × 1/40 × 1 = 18/40
Subtract the two like fractions:
168/40 - 18/40 = 168 - 18/40 = 150/40
After reducing the fraction, the answer is 15/4
In mixed form: 33/4

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