Subtract 6/9 from 90/21, Solve 4 6/21

Subtract 6/9 from 90/21

1^st number: 4 6/21, 2^nd number: 6/9

90/21 - 6/9 is 76/21.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 9 is 63

Next, find the equivalent fraction of both fractional numbers with denominator 63
For the 1st fraction, since 21 × 3 = 63,
90/21 = 90 × 3/21 × 3 = 270/63
Likewise, for the 2nd fraction, since 9 × 7 = 63,
6/9 = 6 × 7/9 × 7 = 42/63
Subtract the two like fractions:
270/63 - 42/63 = 270 - 42/63 = 228/63
After reducing the fraction, the answer is 76/21
In mixed form: 313/21

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