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Finding the Fourth Proportional to 385.28, 578 and 308.64

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Solution

The fourth proportional to 385.28, 578 and 308.64 is: 463.02

Step by Step Solution

  1. Step 1: Write the proportion equation
    385.28 : 578 = 308.64 : x
  2. Step 2: Convert to fraction form
    385.28/578 = 308.64/x
  3. Step 3: Cross multiply
    385.28x = 578 × 308.64
  4. Step 4: Simplify right side
    385.28x = 178,393.92
  5. Step 5: Solve for x
    x = 178,393.92/385.28
  6. Step 6: Final answer
    x = 463.02

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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.