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Finding the Fourth Proportional to 457.30, 685.95 and 213.85

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Solution

The fourth proportional to 457.30, 685.95 and 213.85 is: 320.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    457.30 : 685.95 = 213.85 : x
  2. Step 2: Convert to fraction form
    457.30/685.95 = 213.85/x
  3. Step 3: Cross multiply
    457.30x = 685.95 × 213.85
  4. Step 4: Simplify right side
    457.30x = 146,690.41
  5. Step 5: Solve for x
    x = 146,690.41/457.30
  6. Step 6: Final answer
    x = 320.78

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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.