Subtract 35/84 from 90/20, Solve 4 10/20

Subtract 35/84 from 90/20

1^st number: 4 10/20, 2^nd number: 35/84

90/20 - 35/84 is 49/12.

Find the least common denominator or LCM of the two denominators:
LCM of 20 and 84 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 20 × 21 = 420,
90/20 = 90 × 21/20 × 21 = 1890/420
Likewise, for the 2nd fraction, since 84 × 5 = 420,
35/84 = 35 × 5/84 × 5 = 175/420
Subtract the two like fractions:
1890/420 - 175/420 = 1890 - 175/420 = 1715/420
After reducing the fraction, the answer is 49/12
In mixed form: 41/12

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