Subtract 42/80 from 21/5, Solve 4 1/5

Subtract 42/80 from 21/5

1^st number: 4 1/5, 2^nd number: 42/80

21/5 - 42/80 is 147/40.

Find the least common denominator or LCM of the two denominators:
LCM of 5 and 80 is 80

Next, find the equivalent fraction of both fractional numbers with denominator 80
For the 1st fraction, since 5 × 16 = 80,
21/5 = 21 × 16/5 × 16 = 336/80
Likewise, for the 2nd fraction, since 80 × 1 = 80,
42/80 = 42 × 1/80 × 1 = 42/80
Subtract the two like fractions:
336/80 - 42/80 = 336 - 42/80 = 294/80
After reducing the fraction, the answer is 147/40
In mixed form: 327/40

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