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Finding the Fourth Proportional to 470.20, 705.31 and 145.79

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Solution

The fourth proportional to 470.20, 705.31 and 145.79 is: 218.69

Step by Step Solution

  1. Step 1: Write the proportion equation
    470.20 : 705.31 = 145.79 : x
  2. Step 2: Convert to fraction form
    470.20/705.31 = 145.79/x
  3. Step 3: Cross multiply
    470.20x = 705.31 × 145.79
  4. Step 4: Simplify right side
    470.20x = 102,828.54
  5. Step 5: Solve for x
    x = 102,828.54/470.20
  6. Step 6: Final answer
    x = 218.69

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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.