Subtract 20/42 from 10/15
10/15 - 20/42 is 4/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 42 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 15 × 14 = 210,
10/15 = 10 × 14/15 × 14 = 140/210 - Likewise, for the 2nd fraction, since 42 × 5 = 210,
20/42 = 20 × 5/42 × 5 = 100/210 - Subtract the two like fractions:
140/210 - 100/210 = 140 - 100/210 = 40/210 - After reducing the fraction, the answer is 4/21
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