Subtract 24/28 from 21/18, Solve 1 3/18

Subtract 24/28 from 21/18

1^st number: 1 3/18, 2^nd number: 24/28

21/18 - 24/28 is 13/42.

Find the least common denominator or LCM of the two denominators:
LCM of 18 and 28 is 252

Next, find the equivalent fraction of both fractional numbers with denominator 252
For the 1st fraction, since 18 × 14 = 252,
21/18 = 21 × 14/18 × 14 = 294/252
Likewise, for the 2nd fraction, since 28 × 9 = 252,
24/28 = 24 × 9/28 × 9 = 216/252
Subtract the two like fractions:
294/252 - 216/252 = 294 - 216/252 = 78/252
After reducing the fraction, the answer is 13/42

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