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Finding the Fourth Proportional to 409.71, 613.55 and 390.96

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Solution

The fourth proportional to 409.71, 613.55 and 390.96 is: 585.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    409.71 : 613.55 = 390.96 : x
  2. Step 2: Convert to fraction form
    409.71/613.55 = 390.96/x
  3. Step 3: Cross multiply
    409.71x = 613.55 × 390.96
  4. Step 4: Simplify right side
    409.71x = 239,875.97
  5. Step 5: Solve for x
    x = 239,875.97/409.71
  6. Step 6: Final answer
    x = 585.48

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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.