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Finding the Fourth Proportional to 645.81, 967.90 and 280.17

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Solution

The fourth proportional to 645.81, 967.90 and 280.17 is: 419.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.81 : 967.90 = 280.17 : x
  2. Step 2: Convert to fraction form
    645.81/967.90 = 280.17/x
  3. Step 3: Cross multiply
    645.81x = 967.90 × 280.17
  4. Step 4: Simplify right side
    645.81x = 271,176.54
  5. Step 5: Solve for x
    x = 271,176.54/645.81
  6. Step 6: Final answer
    x = 419.90

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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.