Subtract 21/40 from 45/27, Solve 1 18/27

Subtract 21/40 from 45/27

1^st number: 1 18/27, 2^nd number: 21/40

45/27 - 21/40 is 137/120.

Find the least common denominator or LCM of the two denominators:
LCM of 27 and 40 is 1080

Next, find the equivalent fraction of both fractional numbers with denominator 1080
For the 1st fraction, since 27 × 40 = 1080,
45/27 = 45 × 40/27 × 40 = 1800/1080
Likewise, for the 2nd fraction, since 40 × 27 = 1080,
21/40 = 21 × 27/40 × 27 = 567/1080
Subtract the two like fractions:
1800/1080 - 567/1080 = 1800 - 567/1080 = 1233/1080
After reducing the fraction, the answer is 137/120
In mixed form: 117/120

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