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Finding the Fourth Proportional to 651.86, 978.02 and 408.10

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Solution

The fourth proportional to 651.86, 978.02 and 408.10 is: 612.29

Step by Step Solution

  1. Step 1: Write the proportion equation
    651.86 : 978.02 = 408.10 : x
  2. Step 2: Convert to fraction form
    651.86/978.02 = 408.10/x
  3. Step 3: Cross multiply
    651.86x = 978.02 × 408.10
  4. Step 4: Simplify right side
    651.86x = 399,129.96
  5. Step 5: Solve for x
    x = 399,129.96/651.86
  6. Step 6: Final answer
    x = 612.29

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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.