Subtract 12/45 from 21/72
21/72 - 12/45 is 1/40.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 45 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 72 × 5 = 360,
21/72 = 21 × 5/72 × 5 = 105/360 - Likewise, for the 2nd fraction, since 45 × 8 = 360,
12/45 = 12 × 8/45 × 8 = 96/360 - Subtract the two like fractions:
105/360 - 96/360 = 105 - 96/360 = 9/360 - After reducing the fraction, the answer is 1/40
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