Subtract 21/42 from 12/15
12/15 - 21/42 is 3/10.
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,
12/15 = 12 × 14/15 × 14 = 168/210 - Likewise, for the 2nd fraction, since 42 × 5 = 210,
21/42 = 21 × 5/42 × 5 = 105/210 - Subtract the two like fractions:
168/210 - 105/210 = 168 - 105/210 = 63/210 - After reducing the fraction, the answer is 3/10
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