Subtract 42/70 from 28/72
28/72 - 42/70 is -19/90.
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,
28/72 = 28 × 35/72 × 35 = 980/2520 - Likewise, for the 2nd fraction, since 70 × 36 = 2520,
42/70 = 42 × 36/70 × 36 = 1512/2520 - Subtract the two like fractions:
980/2520 - 1512/2520 = 980 - 1512/2520 = -532/2520 - After reducing the fraction, the answer is -19/90
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