Subtract 42/80 from 21/8, Solve 2 5/8

Subtract 42/80 from 21/8

1^st number: 2 5/8, 2^nd number: 42/80

21/8 - 42/80 is 21/10.

Find the least common denominator or LCM of the two denominators:
LCM of 8 and 80 is 80

Next, find the equivalent fraction of both fractional numbers with denominator 80
For the 1st fraction, since 8 × 10 = 80,
21/8 = 21 × 10/8 × 10 = 210/80
Likewise, for the 2nd fraction, since 80 × 1 = 80,
42/80 = 42 × 1/80 × 1 = 42/80
Subtract the two like fractions:
210/80 - 42/80 = 210 - 42/80 = 168/80
After reducing the fraction, the answer is 21/10
In mixed form: 21/10

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