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Finding the Fourth Proportional to 455.38, 628.21 and 289.65

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Solution

The fourth proportional to 455.38, 628.21 and 289.65 is: 399.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    455.38 : 628.21 = 289.65 : x
  2. Step 2: Convert to fraction form
    455.38/628.21 = 289.65/x
  3. Step 3: Cross multiply
    455.38x = 628.21 × 289.65
  4. Step 4: Simplify right side
    455.38x = 181,960.35
  5. Step 5: Solve for x
    x = 181,960.35/455.38
  6. Step 6: Final answer
    x = 399.58

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.