Subtract 81/84 from 84/40, Solve 2 4/40

Subtract 81/84 from 84/40

1^st number: 2 4/40, 2^nd number: 81/84

84/40 - 81/84 is 159/140.

Find the least common denominator or LCM of the two denominators:
LCM of 40 and 84 is 840

Next, find the equivalent fraction of both fractional numbers with denominator 840
For the 1st fraction, since 40 × 21 = 840,
84/40 = 84 × 21/40 × 21 = 1764/840
Likewise, for the 2nd fraction, since 84 × 10 = 840,
81/84 = 81 × 10/84 × 10 = 810/840
Subtract the two like fractions:
1764/840 - 810/840 = 1764 - 810/840 = 954/840
After reducing the fraction, the answer is 159/140
In mixed form: 119/140

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