Subtract 3/36 from 42/45
42/45 - 3/36 is 17/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 36 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 36 × 5 = 180,
3/36 = 3 × 5/36 × 5 = 15/180 - Subtract the two like fractions:
168/180 - 15/180 = 168 - 15/180 = 153/180 - After reducing the fraction, the answer is 17/20
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