Subtract 72/21 from 16/90
1st number: 16/90, 2nd number: 3 9/21
16/90 - 72/21 is -1024/315.
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,
16/90 = 16 × 7/90 × 7 = 112/630 - Likewise, for the 2nd fraction, since 21 × 30 = 630,
72/21 = 72 × 30/21 × 30 = 2160/630 - Subtract the two like fractions:
112/630 - 2160/630 = 112 - 2160/630 = -2048/630 - After reducing the fraction, the answer is -1024/315
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