Subtract 18/45 from 21/8
1st number: 2 5/8, 2nd number: 18/45
21/8 - 18/45 is 89/40.
Steps for subtracting fractions
- 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,
21/8 = 21 × 45/8 × 45 = 945/360 - Likewise, for the 2nd fraction, since 45 × 8 = 360,
18/45 = 18 × 8/45 × 8 = 144/360 - Subtract the two like fractions:
945/360 - 144/360 = 945 - 144/360 = 801/360 - After reducing the fraction, the answer is 89/40
- In mixed form: 29/40
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