Subtract 70/21 from 90/2, Solve 45 0/2

Subtract 70/21 from 90/2

1^st number: 45 0/2, 2^nd number: 3 7/21

90/2 - 70/21 is 125/3.

Find the least common denominator or LCM of the two denominators:
LCM of 2 and 21 is 42

Next, find the equivalent fraction of both fractional numbers with denominator 42
For the 1st fraction, since 2 × 21 = 42,
90/2 = 90 × 21/2 × 21 = 1890/42
Likewise, for the 2nd fraction, since 21 × 2 = 42,
70/21 = 70 × 2/21 × 2 = 140/42
Subtract the two like fractions:
1890/42 - 140/42 = 1890 - 140/42 = 1750/42
After reducing the fraction, the answer is 125/3
In mixed form: 412/3

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