Subtract 20/35 from 15/21
15/21 - 20/35 is 1/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 35 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 21 × 5 = 105,
15/21 = 15 × 5/21 × 5 = 75/105 - Likewise, for the 2nd fraction, since 35 × 3 = 105,
20/35 = 20 × 3/35 × 3 = 60/105 - Subtract the two like fractions:
75/105 - 60/105 = 75 - 60/105 = 15/105 - After reducing the fraction, the answer is 1/7
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