Subtract 21/70 from 12/72
12/72 - 21/70 is -2/15.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 70 is 2520
Next, find the equivalent fraction of both fractional numbers with denominator 2520 - For the 1st fraction, since 72 × 35 = 2520,
12/72 = 12 × 35/72 × 35 = 420/2520 - Likewise, for the 2nd fraction, since 70 × 36 = 2520,
21/70 = 21 × 36/70 × 36 = 756/2520 - Subtract the two like fractions:
420/2520 - 756/2520 = 420 - 756/2520 = -336/2520 - After reducing the fraction, the answer is -2/15
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