Subtract 90/42 from 28/35, Solve 28/35

Subtract 90/42 from 28/35

1^st number: 28/35, 2^nd number: 2 6/42

28/35 - 90/42 is -47/35.

Find the least common denominator or LCM of the two denominators:
LCM of 35 and 42 is 210

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 35 × 6 = 210,
28/35 = 28 × 6/35 × 6 = 168/210
Likewise, for the 2nd fraction, since 42 × 5 = 210,
90/42 = 90 × 5/42 × 5 = 450/210
Subtract the two like fractions:
168/210 - 450/210 = 168 - 450/210 = -282/210
After reducing the fraction, the answer is -47/35

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