Subtract 42/72 from 40/20
1st number: 2 0/20, 2nd number: 42/72
40/20 - 42/72 is 17/12.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 72 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 20 × 18 = 360,
40/20 = 40 × 18/20 × 18 = 720/360 - Likewise, for the 2nd fraction, since 72 × 5 = 360,
42/72 = 42 × 5/72 × 5 = 210/360 - Subtract the two like fractions:
720/360 - 210/360 = 720 - 210/360 = 510/360 - After reducing the fraction, the answer is 17/12
- In mixed form: 15/12
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