Subtract 4/90 from 21/84
21/84 - 4/90 is 37/180.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 90 is 1260
Next, find the equivalent fraction of both fractional numbers with denominator 1260 - For the 1st fraction, since 84 × 15 = 1260,
21/84 = 21 × 15/84 × 15 = 315/1260 - Likewise, for the 2nd fraction, since 90 × 14 = 1260,
4/90 = 4 × 14/90 × 14 = 56/1260 - Subtract the two like fractions:
315/1260 - 56/1260 = 315 - 56/1260 = 259/1260 - After reducing the fraction, the answer is 37/180
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