Subtract 2/21 from 45/90
45/90 - 2/21 is 17/42.
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,
45/90 = 45 × 7/90 × 7 = 315/630 - Likewise, for the 2nd fraction, since 21 × 30 = 630,
2/21 = 2 × 30/21 × 30 = 60/630 - Subtract the two like fractions:
315/630 - 60/630 = 315 - 60/630 = 255/630 - After reducing the fraction, the answer is 17/42
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