Subtract 72/90 from 81/75, Solve 1 6/75

Subtract 72/90 from 81/75

1^st number: 1 6/75, 2^nd number: 72/90

81/75 - 72/90 is 7/25.

Find the least common denominator or LCM of the two denominators:
LCM of 75 and 90 is 450

Next, find the equivalent fraction of both fractional numbers with denominator 450
For the 1st fraction, since 75 × 6 = 450,
81/75 = 81 × 6/75 × 6 = 486/450
Likewise, for the 2nd fraction, since 90 × 5 = 450,
72/90 = 72 × 5/90 × 5 = 360/450
Subtract the two like fractions:
486/450 - 360/450 = 486 - 360/450 = 126/450
After reducing the fraction, the answer is 7/25

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