Subtract 70/21 from 4/90
1st number: 4/90, 2nd number: 3 7/21
4/90 - 70/21 is -148/45.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 21 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 90 × 7 = 630,
4/90 = 4 × 7/90 × 7 = 28/630 - Likewise, for the 2nd fraction, since 21 × 30 = 630,
70/21 = 70 × 30/21 × 30 = 2100/630 - Subtract the two like fractions:
28/630 - 2100/630 = 28 - 2100/630 = -2072/630 - After reducing the fraction, the answer is -148/45
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