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Finding the Fourth Proportional to 420.11, 628.98 and 317.07

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Solution

The fourth proportional to 420.11, 628.98 and 317.07 is: 474.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.11 : 628.98 = 317.07 : x
  2. Step 2: Convert to fraction form
    420.11/628.98 = 317.07/x
  3. Step 3: Cross multiply
    420.11x = 628.98 × 317.07
  4. Step 4: Simplify right side
    420.11x = 199,430.69
  5. Step 5: Solve for x
    x = 199,430.69/420.11
  6. Step 6: Final answer
    x = 474.71

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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.