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A centipede was crawling in a straight l...

A centipede was crawling in a straight line. First it crawled for `8 (3)/(7)` inch, then it crawled in the reverse direction for `5 (5)/(8)` inch. Once again it reversed direction and crawled for `11 (1)/(2)` inch in the original direction. How far away was it finally from the starting point?

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To find out how far the centipede is from the starting point after crawling in different directions, we can break down the problem step by step. ### Step 1: Convert Mixed Numbers to Improper Fractions First, we need to convert the mixed numbers into improper fractions for easier calculations. 1. **For `8 (3/7)`**: - Convert: \( 8 \times 7 + 3 = 56 + 3 = 59 \) - So, \( 8 \frac{3}{7} = \frac{59}{7} \) 2. **For `5 (5/8)`**: - Convert: \( 5 \times 8 + 5 = 40 + 5 = 45 \) - So, \( 5 \frac{5}{8} = \frac{45}{8} \) 3. **For `11 (1/2)`**: - Convert: \( 11 \times 2 + 1 = 22 + 1 = 23 \) - So, \( 11 \frac{1}{2} = \frac{23}{2} \) ### Step 2: Set Up the Equation Now we can set up the equation based on the movements of the centipede: - First, it crawls forward: \( \frac{59}{7} \) - Then it crawls backward: \( -\frac{45}{8} \) - Finally, it crawls forward again: \( +\frac{23}{2} \) The total distance from the starting point is: \[ \text{Total distance} = \frac{59}{7} - \frac{45}{8} + \frac{23}{2} \] ### Step 3: Find a Common Denominator To perform the addition and subtraction, we need a common denominator. The least common multiple (LCM) of 7, 8, and 2 is 56. - Convert each fraction: 1. \( \frac{59}{7} = \frac{59 \times 8}{7 \times 8} = \frac{472}{56} \) 2. \( \frac{45}{8} = \frac{45 \times 7}{8 \times 7} = \frac{315}{56} \) 3. \( \frac{23}{2} = \frac{23 \times 28}{2 \times 28} = \frac{644}{56} \) ### Step 4: Combine the Fractions Now we can combine the fractions: \[ \text{Total distance} = \frac{472}{56} - \frac{315}{56} + \frac{644}{56} \] Combine the numerators: \[ = \frac{472 - 315 + 644}{56} = \frac{801}{56} \] ### Step 5: Convert to Mixed Number Now convert \( \frac{801}{56} \) into a mixed number: - Divide 801 by 56: - 801 ÷ 56 = 14 remainder 17 So, \( \frac{801}{56} = 14 \frac{17}{56} \). ### Final Answer The centipede is \( 14 \frac{17}{56} \) inches away from the starting point. ---
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