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Finding the Fourth Proportional to 457.09, 685.63 and 429.78

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Solution

The fourth proportional to 457.09, 685.63 and 429.78 is: 644.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    457.09 : 685.63 = 429.78 : x
  2. Step 2: Convert to fraction form
    457.09/685.63 = 429.78/x
  3. Step 3: Cross multiply
    457.09x = 685.63 × 429.78
  4. Step 4: Simplify right side
    457.09x = 294,673.17
  5. Step 5: Solve for x
    x = 294,673.17/457.09
  6. Step 6: Final answer
    x = 644.68

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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.