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Finding the Fourth Proportional to 420.87, 630.25 and 266.33

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Solution

The fourth proportional to 420.87, 630.25 and 266.33 is: 398.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.87 : 630.25 = 266.33 : x
  2. Step 2: Convert to fraction form
    420.87/630.25 = 266.33/x
  3. Step 3: Cross multiply
    420.87x = 630.25 × 266.33
  4. Step 4: Simplify right side
    420.87x = 167,854.48
  5. Step 5: Solve for x
    x = 167,854.48/420.87
  6. Step 6: Final answer
    x = 398.83

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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.