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Finding the Fourth Proportional to 658.92, 988.71 and 399.45

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Solution

The fourth proportional to 658.92, 988.71 and 399.45 is: 599.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    658.92 : 988.71 = 399.45 : x
  2. Step 2: Convert to fraction form
    658.92/988.71 = 399.45/x
  3. Step 3: Cross multiply
    658.92x = 988.71 × 399.45
  4. Step 4: Simplify right side
    658.92x = 394,940.21
  5. Step 5: Solve for x
    x = 394,940.21/658.92
  6. Step 6: Final answer
    x = 599.38

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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.