Subtract 21/45 from 18/8, Solve 2 2/8

Subtract 21/45 from 18/8

1^st number: 2 2/8, 2^nd number: 21/45

18/8 - 21/45 is 107/60.

Find the least common denominator or LCM of the two denominators:
LCM of 8 and 45 is 360

Next, find the equivalent fraction of both fractional numbers with denominator 360
For the 1st fraction, since 8 × 45 = 360,
18/8 = 18 × 45/8 × 45 = 810/360
Likewise, for the 2nd fraction, since 45 × 8 = 360,
21/45 = 21 × 8/45 × 8 = 168/360
Subtract the two like fractions:
810/360 - 168/360 = 810 - 168/360 = 642/360
After reducing the fraction, the answer is 107/60
In mixed form: 147/60

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