Subtract 2/90 from 42/21, Solve 2 0/21

Subtract 2/90 from 42/21

1^st number: 2 0/21, 2^nd number: 2/90

42/21 - 2/90 is 89/45.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 90 is 630

Next, find the equivalent fraction of both fractional numbers with denominator 630
For the 1st fraction, since 21 × 30 = 630,
42/21 = 42 × 30/21 × 30 = 1260/630
Likewise, for the 2nd fraction, since 90 × 7 = 630,
2/90 = 2 × 7/90 × 7 = 14/630
Subtract the two like fractions:
1260/630 - 14/630 = 1260 - 14/630 = 1246/630
After reducing the fraction, the answer is 89/45
In mixed form: 144/45

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