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Finding the Fourth Proportional to 390.54, 581.50 and 384.70

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Solution

The fourth proportional to 390.54, 581.50 and 384.70 is: 572.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    390.54 : 581.50 = 384.70 : x
  2. Step 2: Convert to fraction form
    390.54/581.50 = 384.70/x
  3. Step 3: Cross multiply
    390.54x = 581.50 × 384.70
  4. Step 4: Simplify right side
    390.54x = 223,703.05
  5. Step 5: Solve for x
    x = 223,703.05/390.54
  6. Step 6: Final answer
    x = 572.80

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.