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Finding the Fourth Proportional to 470.21, 705.31 and 287.65

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Solution

The fourth proportional to 470.21, 705.31 and 287.65 is: 431.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    470.21 : 705.31 = 287.65 : x
  2. Step 2: Convert to fraction form
    470.21/705.31 = 287.65/x
  3. Step 3: Cross multiply
    470.21x = 705.31 × 287.65
  4. Step 4: Simplify right side
    470.21x = 202,882.58
  5. Step 5: Solve for x
    x = 202,882.58/470.21
  6. Step 6: Final answer
    x = 431.48

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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.