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Finding the Fourth Proportional to 289.80, 406.80 and 289.80

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Solution

The fourth proportional to 289.80, 406.80 and 289.80 is: 406.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    289.80 : 406.80 = 289.80 : x
  2. Step 2: Convert to fraction form
    289.80/406.80 = 289.80/x
  3. Step 3: Cross multiply
    289.80x = 406.80 × 289.80
  4. Step 4: Simplify right side
    289.80x = 117,890.64
  5. Step 5: Solve for x
    x = 117,890.64/289.80
  6. Step 6: Final answer
    x = 406.80

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Why These Related Problems?

These problems maintain the same ratio (1.40) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.