Subtract 1/30 from 21/72
21/72 - 1/30 is 31/120.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 30 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 30 × 12 = 360,
1/30 = 1 × 12/30 × 12 = 12/360 - Subtract the two like fractions:
105/360 - 12/360 = 105 - 12/360 = 93/360 - After reducing the fraction, the answer is 31/120
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