Subtract 10/40 from 40/42, Solve 40/42

Subtract 10/40 from 40/42

40/42 - 10/40 is 59/84.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 40 is 840

Next, find the equivalent fraction of both fractional numbers with denominator 840
For the 1st fraction, since 42 × 20 = 840,
40/42 = 40 × 20/42 × 20 = 800/840
Likewise, for the 2nd fraction, since 40 × 21 = 840,
10/40 = 10 × 21/40 × 21 = 210/840
Subtract the two like fractions:
800/840 - 210/840 = 800 - 210/840 = 590/840
After reducing the fraction, the answer is 59/84

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