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Finding the Fourth Proportional to 381.10, 571.65 and 208.30

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Solution

The fourth proportional to 381.10, 571.65 and 208.30 is: 312.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    381.10 : 571.65 = 208.30 : x
  2. Step 2: Convert to fraction form
    381.10/571.65 = 208.30/x
  3. Step 3: Cross multiply
    381.10x = 571.65 × 208.30
  4. Step 4: Simplify right side
    381.10x = 119,074.70
  5. Step 5: Solve for x
    x = 119,074.70/381.10
  6. Step 6: Final answer
    x = 312.45

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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.