Subtract 9/42 from 21/35
21/35 - 9/42 is 27/70.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 35 and 42 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 35 × 6 = 210,
21/35 = 21 × 6/35 × 6 = 126/210 - Likewise, for the 2nd fraction, since 42 × 5 = 210,
9/42 = 9 × 5/42 × 5 = 45/210 - Subtract the two like fractions:
126/210 - 45/210 = 126 - 45/210 = 81/210 - After reducing the fraction, the answer is 27/70
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