Subtract 7/20 from 3/45
3/45 - 7/20 is -17/60.
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,
3/45 = 3 × 4/45 × 4 = 12/180 - Likewise, for the 2nd fraction, since 20 × 9 = 180,
7/20 = 7 × 9/20 × 9 = 63/180 - Subtract the two like fractions:
12/180 - 63/180 = 12 - 63/180 = -51/180 - After reducing the fraction, the answer is -17/60
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