Subtract 72/81 from 10/80
10/80 - 72/81 is -55/72.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 81 is 6480
Next, find the equivalent fraction of both fractional numbers with denominator 6480 - For the 1st fraction, since 80 × 81 = 6480,
10/80 = 10 × 81/80 × 81 = 810/6480 - Likewise, for the 2nd fraction, since 81 × 80 = 6480,
72/81 = 72 × 80/81 × 80 = 5760/6480 - Subtract the two like fractions:
810/6480 - 5760/6480 = 810 - 5760/6480 = -4950/6480 - After reducing the fraction, the answer is -55/72
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