Subtract 10/21 from 90/45, Solve 2 0/45

Subtract 10/21 from 90/45

1^st number: 2 0/45, 2^nd number: 10/21

90/45 - 10/21 is 32/21.

Find the least common denominator or LCM of the two denominators:
LCM of 45 and 21 is 315

Next, find the equivalent fraction of both fractional numbers with denominator 315
For the 1st fraction, since 45 × 7 = 315,
90/45 = 90 × 7/45 × 7 = 630/315
Likewise, for the 2nd fraction, since 21 × 15 = 315,
10/21 = 10 × 15/21 × 15 = 150/315
Subtract the two like fractions:
630/315 - 150/315 = 630 - 150/315 = 480/315
After reducing the fraction, the answer is 32/21
In mixed form: 111/21

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