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Finding the Fourth Proportional to 665.11, 917.87 and 370.40

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Solution

The fourth proportional to 665.11, 917.87 and 370.40 is: 511.16

Step by Step Solution

  1. Step 1: Write the proportion equation
    665.11 : 917.87 = 370.40 : x
  2. Step 2: Convert to fraction form
    665.11/917.87 = 370.40/x
  3. Step 3: Cross multiply
    665.11x = 917.87 × 370.40
  4. Step 4: Simplify right side
    665.11x = 339,979.05
  5. Step 5: Solve for x
    x = 339,979.05/665.11
  6. Step 6: Final answer
    x = 511.16

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.