Subtract 90/35 from 21/72
1st number: 21/72, 2nd number: 2 20/35
21/72 - 90/35 is -383/168.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 35 is 2520
Next, find the equivalent fraction of both fractional numbers with denominator 2520 - For the 1st fraction, since 72 × 35 = 2520,
21/72 = 21 × 35/72 × 35 = 735/2520 - Likewise, for the 2nd fraction, since 35 × 72 = 2520,
90/35 = 90 × 72/35 × 72 = 6480/2520 - Subtract the two like fractions:
735/2520 - 6480/2520 = 735 - 6480/2520 = -5745/2520 - After reducing the fraction, the answer is -383/168
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