Subtract 12/90 from 40/42
40/42 - 12/90 is 86/105.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 90 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 42 × 15 = 630,
40/42 = 40 × 15/42 × 15 = 600/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
12/90 = 12 × 7/90 × 7 = 84/630 - Subtract the two like fractions:
600/630 - 84/630 = 600 - 84/630 = 516/630 - After reducing the fraction, the answer is 86/105
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