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Finding the Fourth Proportional to 390.69, 541.62 and 369.89

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Solution

The fourth proportional to 390.69, 541.62 and 369.89 is: 512.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    390.69 : 541.62 = 369.89 : x
  2. Step 2: Convert to fraction form
    390.69/541.62 = 369.89/x
  3. Step 3: Cross multiply
    390.69x = 541.62 × 369.89
  4. Step 4: Simplify right side
    390.69x = 200,337.11
  5. Step 5: Solve for x
    x = 200,337.11/390.69
  6. Step 6: Final answer
    x = 512.78

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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.