Subtract 21/70 from 90/72
1st number: 1 18/72, 2nd number: 21/70
90/72 - 21/70 is 19/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 70 is 2520
Next, find the equivalent fraction of both fractional numbers with denominator 2520 - For the 1st fraction, since 72 × 35 = 2520,
90/72 = 90 × 35/72 × 35 = 3150/2520 - Likewise, for the 2nd fraction, since 70 × 36 = 2520,
21/70 = 21 × 36/70 × 36 = 756/2520 - Subtract the two like fractions:
3150/2520 - 756/2520 = 3150 - 756/2520 = 2394/2520 - After reducing the fraction, the answer is 19/20
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