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Finding the Fourth Proportional to 865.10, 1,298.25 and 345.05

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Solution

The fourth proportional to 865.10, 1,298.25 and 345.05 is: 517.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    865.10 : 1,298.25 = 345.05 : x
  2. Step 2: Convert to fraction form
    865.10/1,298.25 = 345.05/x
  3. Step 3: Cross multiply
    865.10x = 1,298.25 × 345.05
  4. Step 4: Simplify right side
    865.10x = 447,958.25
  5. Step 5: Solve for x
    x = 447,958.25/865.10
  6. Step 6: Final answer
    x = 517.81

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.