Subtract 4/90 from 40/42
40/42 - 4/90 is 286/315.
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,
4/90 = 4 × 7/90 × 7 = 28/630 - Subtract the two like fractions:
600/630 - 28/630 = 600 - 28/630 = 572/630 - After reducing the fraction, the answer is 286/315
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