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Finding the Fourth Proportional to 619.81, 929.41 and 208.87

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Solution

The fourth proportional to 619.81, 929.41 and 208.87 is: 313.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    619.81 : 929.41 = 208.87 : x
  2. Step 2: Convert to fraction form
    619.81/929.41 = 208.87/x
  3. Step 3: Cross multiply
    619.81x = 929.41 × 208.87
  4. Step 4: Simplify right side
    619.81x = 194,123.02
  5. Step 5: Solve for x
    x = 194,123.02/619.81
  6. Step 6: Final answer
    x = 313.20

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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.