Subtract 10/20 from 42/45
42/45 - 10/20 is 13/30.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 20 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 45 × 4 = 180,
42/45 = 42 × 4/45 × 4 = 168/180 - Likewise, for the 2nd fraction, since 20 × 9 = 180,
10/20 = 10 × 9/20 × 9 = 90/180 - Subtract the two like fractions:
168/180 - 90/180 = 168 - 90/180 = 78/180 - After reducing the fraction, the answer is 13/30
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