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Finding the Fourth Proportional to 457.20, 685.71 and 213.66

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Solution

The fourth proportional to 457.20, 685.71 and 213.66 is: 320.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    457.20 : 685.71 = 213.66 : x
  2. Step 2: Convert to fraction form
    457.20/685.71 = 213.66/x
  3. Step 3: Cross multiply
    457.20x = 685.71 × 213.66
  4. Step 4: Simplify right side
    457.20x = 146,508.80
  5. Step 5: Solve for x
    x = 146,508.80/457.20
  6. Step 6: Final answer
    x = 320.45

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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.