Subtract 9/5 from 90/84, Solve 1 6/84

Subtract 9/5 from 90/84

1^st number: 1 6/84, 2^nd number: 1 4/5

90/84 - 9/5 is -51/70.

Find the least common denominator or LCM of the two denominators:
LCM of 84 and 5 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 84 × 5 = 420,
90/84 = 90 × 5/84 × 5 = 450/420
Likewise, for the 2nd fraction, since 5 × 84 = 420,
9/5 = 9 × 84/5 × 84 = 756/420
Subtract the two like fractions:
450/420 - 756/420 = 450 - 756/420 = -306/420
After reducing the fraction, the answer is -51/70

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