Subtract 18/72 from 81/50, Solve 1 31/50

Subtract 18/72 from 81/50

1^st number: 1 31/50, 2^nd number: 18/72

81/50 - 18/72 is 137/100.

Find the least common denominator or LCM of the two denominators:
LCM of 50 and 72 is 1800

Next, find the equivalent fraction of both fractional numbers with denominator 1800
For the 1st fraction, since 50 × 36 = 1800,
81/50 = 81 × 36/50 × 36 = 2916/1800
Likewise, for the 2nd fraction, since 72 × 25 = 1800,
18/72 = 18 × 25/72 × 25 = 450/1800
Subtract the two like fractions:
2916/1800 - 450/1800 = 2916 - 450/1800 = 2466/1800
After reducing the fraction, the answer is 137/100
In mixed form: 137/100

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