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

Subtract 42/80 from 21/4

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

21/4 - 42/80 is 189/40.

Find the least common denominator or LCM of the two denominators:
LCM of 4 and 80 is 80

Next, find the equivalent fraction of both fractional numbers with denominator 80
For the 1st fraction, since 4 × 20 = 80,
21/4 = 21 × 20/4 × 20 = 420/80
Likewise, for the 2nd fraction, since 80 × 1 = 80,
42/80 = 42 × 1/80 × 1 = 42/80
Subtract the two like fractions:
420/80 - 42/80 = 420 - 42/80 = 378/80
After reducing the fraction, the answer is 189/40
In mixed form: 429/40

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