Subtract 21/10 from 40/72
1st number: 40/72, 2nd number: 2 1/10
40/72 - 21/10 is -139/90.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 10 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 72 × 5 = 360,
40/72 = 40 × 5/72 × 5 = 200/360 - Likewise, for the 2nd fraction, since 10 × 36 = 360,
21/10 = 21 × 36/10 × 36 = 756/360 - Subtract the two like fractions:
200/360 - 756/360 = 200 - 756/360 = -556/360 - After reducing the fraction, the answer is -139/90
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