Subtract 28/45 from 21/14, Solve 1 7/14

Subtract 28/45 from 21/14

1^st number: 1 7/14, 2^nd number: 28/45

21/14 - 28/45 is 79/90.

Find the least common denominator or LCM of the two denominators:
LCM of 14 and 45 is 630

Next, find the equivalent fraction of both fractional numbers with denominator 630
For the 1st fraction, since 14 × 45 = 630,
21/14 = 21 × 45/14 × 45 = 945/630
Likewise, for the 2nd fraction, since 45 × 14 = 630,
28/45 = 28 × 14/45 × 14 = 392/630
Subtract the two like fractions:
945/630 - 392/630 = 945 - 392/630 = 553/630
After reducing the fraction, the answer is 79/90

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