Subtract 15/8 from 21/45
1st number: 21/45, 2nd number: 1 7/8
21/45 - 15/8 is -169/120.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 8 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 45 × 8 = 360,
21/45 = 21 × 8/45 × 8 = 168/360 - Likewise, for the 2nd fraction, since 8 × 45 = 360,
15/8 = 15 × 45/8 × 45 = 675/360 - Subtract the two like fractions:
168/360 - 675/360 = 168 - 675/360 = -507/360 - After reducing the fraction, the answer is -169/120
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