Subtract 2/40 from 20/42, Solve 20/42

Subtract 2/40 from 20/42

20/42 - 2/40 is 179/420.

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,
20/42 = 20 × 20/42 × 20 = 400/840
Likewise, for the 2nd fraction, since 40 × 21 = 840,
2/40 = 2 × 21/40 × 21 = 42/840
Subtract the two like fractions:
400/840 - 42/840 = 400 - 42/840 = 358/840
After reducing the fraction, the answer is 179/420

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