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Finding the Fourth Proportional to 384.10, 528.78 and 285.70

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Solution

The fourth proportional to 384.10, 528.78 and 285.70 is: 393.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    384.10 : 528.78 = 285.70 : x
  2. Step 2: Convert to fraction form
    384.10/528.78 = 285.70/x
  3. Step 3: Cross multiply
    384.10x = 528.78 × 285.70
  4. Step 4: Simplify right side
    384.10x = 151,072.45
  5. Step 5: Solve for x
    x = 151,072.45/384.10
  6. Step 6: Final answer
    x = 393.32

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.