Subtract 42/40 from 28/10, Solve 2 8/10

Subtract 42/40 from 28/10

1^st number: 2 8/10, 2^nd number: 1 2/40

28/10 - 42/40 is 7/4.

Find the least common denominator or LCM of the two denominators:
LCM of 10 and 40 is 40

Next, find the equivalent fraction of both fractional numbers with denominator 40
For the 1st fraction, since 10 × 4 = 40,
28/10 = 28 × 4/10 × 4 = 112/40
Likewise, for the 2nd fraction, since 40 × 1 = 40,
42/40 = 42 × 1/40 × 1 = 42/40
Subtract the two like fractions:
112/40 - 42/40 = 112 - 42/40 = 70/40
After reducing the fraction, the answer is 7/4
In mixed form: 13/4

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