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Finding the Fourth Proportional to 390.55, 585.39 and 299.62

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Solution

The fourth proportional to 390.55, 585.39 and 299.62 is: 449.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    390.55 : 585.39 = 299.62 : x
  2. Step 2: Convert to fraction form
    390.55/585.39 = 299.62/x
  3. Step 3: Cross multiply
    390.55x = 585.39 × 299.62
  4. Step 4: Simplify right side
    390.55x = 175,394.55
  5. Step 5: Solve for x
    x = 175,394.55/390.55
  6. Step 6: Final answer
    x = 449.10

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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.