Subtract 4/90 from 21/7, Solve 3 0/7

Subtract 4/90 from 21/7

1^st number: 3 0/7, 2^nd number: 4/90

21/7 - 4/90 is 133/45.

Find the least common denominator or LCM of the two denominators:
LCM of 7 and 90 is 630

Next, find the equivalent fraction of both fractional numbers with denominator 630
For the 1st fraction, since 7 × 90 = 630,
21/7 = 21 × 90/7 × 90 = 1890/630
Likewise, for the 2nd fraction, since 90 × 7 = 630,
4/90 = 4 × 7/90 × 7 = 28/630
Subtract the two like fractions:
1890/630 - 28/630 = 1890 - 28/630 = 1862/630
After reducing the fraction, the answer is 133/45
In mixed form: 243/45

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