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Finding the Fourth Proportional to 423.90, 636.12 and 287.28

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Solution

The fourth proportional to 423.90, 636.12 and 287.28 is: 431.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    423.90 : 636.12 = 287.28 : x
  2. Step 2: Convert to fraction form
    423.90/636.12 = 287.28/x
  3. Step 3: Cross multiply
    423.90x = 636.12 × 287.28
  4. Step 4: Simplify right side
    423.90x = 182,744.55
  5. Step 5: Solve for x
    x = 182,744.55/423.90
  6. Step 6: Final answer
    x = 431.10

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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.