Subtract 3/84 from 30/40, Solve 30/40

Subtract 3/84 from 30/40

30/40 - 3/84 is 5/7.

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,
30/40 = 30 × 21/40 × 21 = 630/840
Likewise, for the 2nd fraction, since 84 × 10 = 840,
3/84 = 3 × 10/84 × 10 = 30/840
Subtract the two like fractions:
630/840 - 30/840 = 630 - 30/840 = 600/840
After reducing the fraction, the answer is 5/7

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