Subtract 21/45 from 27/21, Solve 1 6/21

Subtract 21/45 from 27/21

1^st number: 1 6/21, 2^nd number: 21/45

27/21 - 21/45 is 86/105.

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

Next, find the equivalent fraction of both fractional numbers with denominator 315
For the 1st fraction, since 21 × 15 = 315,
27/21 = 27 × 15/21 × 15 = 405/315
Likewise, for the 2nd fraction, since 45 × 7 = 315,
21/45 = 21 × 7/45 × 7 = 147/315
Subtract the two like fractions:
405/315 - 147/315 = 405 - 147/315 = 258/315
After reducing the fraction, the answer is 86/105

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