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Finding the Fourth Proportional to 280.29, 420.20 and 164.85

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Solution

The fourth proportional to 280.29, 420.20 and 164.85 is: 247.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.29 : 420.20 = 164.85 : x
  2. Step 2: Convert to fraction form
    280.29/420.20 = 164.85/x
  3. Step 3: Cross multiply
    280.29x = 420.20 × 164.85
  4. Step 4: Simplify right side
    280.29x = 69,269.15
  5. Step 5: Solve for x
    x = 69,269.15/280.29
  6. Step 6: Final answer
    x = 247.13

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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.