Subtract 81/84 from 28/10, Solve 2 8/10

Subtract 81/84 from 28/10

1^st number: 2 8/10, 2^nd number: 81/84

28/10 - 81/84 is 257/140.

Find the least common denominator or LCM of the two denominators:
LCM of 10 and 84 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 10 × 42 = 420,
28/10 = 28 × 42/10 × 42 = 1176/420
Likewise, for the 2nd fraction, since 84 × 5 = 420,
81/84 = 81 × 5/84 × 5 = 405/420
Subtract the two like fractions:
1176/420 - 405/420 = 1176 - 405/420 = 771/420
After reducing the fraction, the answer is 257/140
In mixed form: 1117/140

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