Subtract 21/16 from 70/90
1st number: 70/90, 2nd number: 1 5/16
70/90 - 21/16 is -77/144.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 16 is 720
Next, find the equivalent fraction of both fractional numbers with denominator 720 - For the 1st fraction, since 90 × 8 = 720,
70/90 = 70 × 8/90 × 8 = 560/720 - Likewise, for the 2nd fraction, since 16 × 45 = 720,
21/16 = 21 × 45/16 × 45 = 945/720 - Subtract the two like fractions:
560/720 - 945/720 = 560 - 945/720 = -385/720 - After reducing the fraction, the answer is -77/144
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