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Finding the Fourth Proportional to 651.38, 978.58 and 408.08

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Solution

The fourth proportional to 651.38, 978.58 and 408.08 is: 613.07

Step by Step Solution

  1. Step 1: Write the proportion equation
    651.38 : 978.58 = 408.08 : x
  2. Step 2: Convert to fraction form
    651.38/978.58 = 408.08/x
  3. Step 3: Cross multiply
    651.38x = 978.58 × 408.08
  4. Step 4: Simplify right side
    651.38x = 399,338.93
  5. Step 5: Solve for x
    x = 399,338.93/651.38
  6. Step 6: Final answer
    x = 613.07

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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.