Subtract 20/50 from 42/45
42/45 - 20/50 is 8/15.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 50 is 450
Next, find the equivalent fraction of both fractional numbers with denominator 450 - For the 1st fraction, since 45 × 10 = 450,
42/45 = 42 × 10/45 × 10 = 420/450 - Likewise, for the 2nd fraction, since 50 × 9 = 450,
20/50 = 20 × 9/50 × 9 = 180/450 - Subtract the two like fractions:
420/450 - 180/450 = 420 - 180/450 = 240/450 - After reducing the fraction, the answer is 8/15
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