Subtract 70/54 from 90/84, Solve 1 6/84

Subtract 70/54 from 90/84

1^st number: 1 6/84, 2^nd number: 1 16/54

90/84 - 70/54 is -85/378.

Find the least common denominator or LCM of the two denominators:
LCM of 84 and 54 is 756

Next, find the equivalent fraction of both fractional numbers with denominator 756
For the 1st fraction, since 84 × 9 = 756,
90/84 = 90 × 9/84 × 9 = 810/756
Likewise, for the 2nd fraction, since 54 × 14 = 756,
70/54 = 70 × 14/54 × 14 = 980/756
Subtract the two like fractions:
810/756 - 980/756 = 810 - 980/756 = -170/756
After reducing the fraction, the answer is -85/378

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