Subtract 4/45 from 21/7, Solve 3 0/7

Subtract 4/45 from 21/7

1^st number: 3 0/7, 2^nd number: 4/45

21/7 - 4/45 is 131/45.

Find the least common denominator or LCM of the two denominators:
LCM of 7 and 45 is 315

Next, find the equivalent fraction of both fractional numbers with denominator 315
For the 1st fraction, since 7 × 45 = 315,
21/7 = 21 × 45/7 × 45 = 945/315
Likewise, for the 2nd fraction, since 45 × 7 = 315,
4/45 = 4 × 7/45 × 7 = 28/315
Subtract the two like fractions:
945/315 - 28/315 = 945 - 28/315 = 917/315
After reducing the fraction, the answer is 131/45
In mixed form: 241/45

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