Subtract 63/21 from 72/80
1st number: 72/80, 2nd number: 3 0/21
72/80 - 63/21 is -21/10.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 21 is 1680
Next, find the equivalent fraction of both fractional numbers with denominator 1680 - For the 1st fraction, since 80 × 21 = 1680,
72/80 = 72 × 21/80 × 21 = 1512/1680 - Likewise, for the 2nd fraction, since 21 × 80 = 1680,
63/21 = 63 × 80/21 × 80 = 5040/1680 - Subtract the two like fractions:
1512/1680 - 5040/1680 = 1512 - 5040/1680 = -3528/1680 - After reducing the fraction, the answer is -21/10
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