Subtract 30/72 from 40/70
40/70 - 30/72 is 13/84.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 72 is 2520
Next, find the equivalent fraction of both fractional numbers with denominator 2520 - For the 1st fraction, since 70 × 36 = 2520,
40/70 = 40 × 36/70 × 36 = 1440/2520 - Likewise, for the 2nd fraction, since 72 × 35 = 2520,
30/72 = 30 × 35/72 × 35 = 1050/2520 - Subtract the two like fractions:
1440/2520 - 1050/2520 = 1440 - 1050/2520 = 390/2520 - After reducing the fraction, the answer is 13/84
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