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Finding the Fourth Proportional to 405.90, 609.15 and 325.71

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Solution

The fourth proportional to 405.90, 609.15 and 325.71 is: 488.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    405.90 : 609.15 = 325.71 : x
  2. Step 2: Convert to fraction form
    405.90/609.15 = 325.71/x
  3. Step 3: Cross multiply
    405.90x = 609.15 × 325.71
  4. Step 4: Simplify right side
    405.90x = 198,406.25
  5. Step 5: Solve for x
    x = 198,406.25/405.90
  6. Step 6: Final answer
    x = 488.81

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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.